If, to invert the cliché, baseball season was a sprint and not a marathon, a couple of Yankees and Mets stars probably already would have pulled hamstrings.

The Yankees are expected to open the season Thursday with three-fifths of their starting rotation — Carlos Rodon, Frankie Montas and Luis Severino — and more than half of their ideal pitching staff — including relievers Lou Trivino, Tommy Kahnle and Scott Effross — on the injured list. Not to mention center fielder Harrison Bader’s absence.

The Mets will be without starter Jose Quintana until at least July and without closer Edwin Diaz for the season. The lineup includes a lot of the same names who combined to hit .185 and managed eight runs during a short stay in the 2022 playoffs, especially with top prospects Brett Baty, Mark Vientos and Francisco Alvarez shipped to the minors and near-addition Carlos Correa swinging for the Twins.

Opening Day is supposed to be that magical time when even fans of the hapless Athletics can look at the standings and think, “This is our year!” But already there is a sense of pessimism around New York about potentially slow starts and what early losses might mean in terms of the Yankees falling behind the pitching-fortified Blue Jays and pesky Rays, and the Mets losing ground to the powerhouse Braves and Phillies.

So, here are reminders that baseball is a marathon. Keep them as a reference point if your favorite team loses the first series of the season. Let’s start close to home:

• The 2022 Mets were in first place for 176 days out of a possible 181, lost a tiebreaker for the division title and lost a three-game Wild Card series against the Padres.

• The 2021 Mets were in first place for 114 days but spiraled after Aug. 13 and finished under .500. Simultaneously, the Braves — spurred by some August trades to make up for the injuries to big bat Ronald Acuna Jr. and pitcher Mike Soroka — seized sole possession of first place for the first time on Aug. 15 and joined the 1964 Cardinals as the only teams ever to win the World Series after being under .500 at the All-Star break, when their odds of reaching the playoffs were about 8 percent.

• The 2019 Nationals were 19-31 after 50 games and stuck in fourth place in the NL East every day from April 24 through June 16 before finishing 93-69 to clinch a Wild Card berth that became a World Series title. The 2014 American League champion Royals were under .500 until June 8, and the 2001 Athletics started 8-17 but still won 102 games and made the playoffs.

• On the other hand, the 2021 and 2022 Dodgers started 15-6 and 12-4, respectively, on the way to a combined 209 regular-season wins — and neither team reached the World Series.

• The MLB record for best starts to a season — 13 straight wins — is shared by the 1982 Braves and 1987 Brewers, neither of whom reached the World Series.

Only 27.6 percent of the teams that have had the best record in a season through 50 games have won the World Series — and the 2022 Yankees were on the wrong side of that stat.

What might help keep these teams afloat in April?

For the Yankees, the search is underway for a tandem like Aaron Small and Shawn Chacon, who saved the 2005 injury-riddled pitching staff by going a combined 17-3.

Maybe that duo is Clarke Schmidt and Jhony Brito, a couple of farmhands who could convince general manager Brian Cashman to stick with homegrown pitchers and stop adding to his dreadful history of acquiring big-name pitchers (see: Carl Pavano, Sonny Gray and Montas).

Then there’s the excitement around shortstop Anthony Volpe, which feels a lot like it did when Derek Jeter homered and made a great over-the-shoulder catch on Opening Day in 1996.

For the Mets, a shaky bullpen might get some breathing room if the trio of Max Scherzer, Justin Verlander and Kodai Senga performs like the best top of the rotation in baseball, and Francisco Lindor, Jeff McNeil and Pete Alonso provide big leads by duplicating their outputs from last regular season.

So, it’s not all doom and gloom no matter how things start. Unless, you are an Athletics fan. Then, at least Steph Curry will be shooting 3s in the NBA playoffs soon.

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Perhaps the most true-to-a-fairytale part of this Cinderella-rich men’s basketball NCAA Tournament is the extermination of hard-to-root-for head coaches.

In Friday’s four Sweet 16 games alone, the losers included:

• Xavier’s Sean Miller, who was fired after last season by Arizona, which he left on three years of NCAA probation. He was accused of a lack of oversight but later absolved of sanctions in the Independent Accountability Resolution Process despite hiring two rule-breaking assistant coaches, including Emanuel Richardson, who “solicited and accepted $20,000 in cash bribes and paid $40,000 for a fraudulent academic transcript.”

• Houston’s Kelvin Sampson was found guilty of making hundreds of impermissible recruiting phone calls while at Oklahoma and Indiana and effectively banned from college basketball coaching for five years — one of the harshest penalties given to an individual in NCAA history.

• Alabama’s Nate Oates is under criticism for allowing future NBA lottery pick Brandon Miller to continue playing despite court testimony identifying him as the one who brought then-teammate Darius Miles the gun that he allegedly used in a fatal shooting. Miller has not been charged by police but Oates’ “wrong place at the wrong time” defense of Miller’s actions reverberates as stomach-turning despite an apology.

It can be hard to find coaches with spotless records these days. Consider it the viewer’s choice to weigh the severity of one alleged transgression against another.

The Elite Eight losers included …

• Creighton’s Greg McDermott, who claimed ignorance when a staff member’s recruiting violations landed the program two years of probation but had nowhere to pass the buck when he was suspended and fined for making racially insensitive remarks to his team two seasons ago.

• Texas’ Rodney Terry, the interim coach of the Longhorns because Chris Beard was fired after an arrest for felony domestic violence. The charge was dropped, and Beard already has resurfaced in charge of Ole Miss.

Just something to keep in mind as bracket pools are decided and a Final Four with a blue-blood No. 1 seed is celebrated.

In an era where college athletics departments are sinking tens of millions into football to chase a pot of gold from television contracts, there is something special about a Final Four that includes only one school (Miami) with a Power Five conference football program.

UConn plays as a FBS football independent so that its other athletes can participate in the non-football-playing Big East, while FAU (Conference USA) and San Diego State (Mountain West) play in Group of Five conferences.

The 2017 NCAA men’s basketball championship game featured Villanova (FCS football) and Gonzaga (no football), but the other Final Four teams were football powers South Carolina out of the SEC and Oregon out of the PAC-12.

If you believe that NFL free-agency signings accidentally telegraph draft picks, then forget about the Giants selecting a receiver in the first round next month.

While receiver is still the consensus among most mock drafters, the Giants have added Parris Campbell, Jeff Smith and Jamison Crowder to a crowded room, while also re-signing Sterling Shepherd and Darius Slayton.

Meanwhile, the secondary will be without Seahawks-bound safety Julian Love and could be without unsigned starting cornerback Fabian Moreau.

So, what if the Giants look to address their defense, specifically the back end, with pick No. 25 in the first round? Who fits coordinator Wink Martindale’s blitz-heavy and press-coverage scheme?

“I see a little bit of [Ravens All-Pro cornerback] Marlon Humphrey in Deonte Banks from Maryland,” ESPN NFL Draft analyst Mel Kiper Jr. said when posed that question by Post Sports+ last week. “He could possibly be there at No. 25.

“He missed most of 2021 with a shoulder [injury]. Came back this year and was breaking up passes, was closing on the ball. He just has to work on the deep ball — just locating the ball. He’s in position — sometimes he just loses sight of the ball. He’ll tackle. He tested really well [at the NFL Combine]. He would be the guy.”

NFL owners will vote on 17 rule changes and other alterations to the league’s bylaws this week at the annual spring owners meetings in Arizona. Among the most dramatic changes a fan would notice next fall are proposals that would allow:

• One fourth-and-20 play from the kicking team’s 20-yard line to be substituted for an onside kick.

• Roughing the passer penalties to be reviewable by replay assist and/or coach’s challenge.

• The ball to be placed at the 25-yard line after fair catches on kickoffs and free kicks inside the 25.

• Teams to dress a third quarterback who can be used in an emergency situation (as to avoid a repeat of the NFC Championship debacle).

• Wild-card playoff teams to host a playoff game if they have four or more wins than a division winner with a losing record

If the one-year experiment with reviewable pass interference penalties in 2019 is any indication, it is a waste to implement the roughing the passer reviews because indignant officials will refuse to reverse most judgment calls.

Only 5.3 percent of onside kickoffs were recovered last season, per The Football Database, so the proposal, while extreme, is at least consistent with other changes to make the game friendlier to offenses, phase out special-teams collisions and keep scores close.

And, of course, one of the biggest changes under consideration is adding a flex scheduling option for Thursday Night Football games held in Weeks 14-17.

A game could be moved from up from Sunday to Thursday with 15 days notice and each team could be forced to play on a Thursday after a Sunday twice instead of once.

Given that the primary reason for this change would be to eliminate Thursday games between losing teams that draw a smaller viewing audience than games with playoff implications, it essentially is the league announcing that it considers its television partners (Amazon, in this case) and not the players to be its primary “business partners.”

It is not adding an extra Thursday night game, however. So, in regards to player safety, more players wouldn’t be put at risk by the quick turnaround from a Sunday to a Thursday game.

Good luck convincing players on good teams that the extra physical toll on their bodies isn’t a penalty for success, however.

And good luck getting coaches on board because injured players who might be available on Sunday but not on Thursday (without extra rest) possibly would miss high-stakes late-season games.

NFL executive vice president Jeff Miller said last week that Thursday flex scheduling is “not a concern from a health and safety perspective” because “over the course of the last several years now, we have not seen a differential injury rate on Thursday night games or, said more precisely, on games played on short rest compared to games played on longer rest.”

At the very least that data deserves a closer look by the public to determine the exact definition of an “injury.”