BALTIMORE — Add another file to Cam Schlittler’s mounting case to be the third Yankees starter in the playoffs. 

The rookie right-hander was sharp again on Sunday, leaning on his improved fastball command to help lead the Yankees to a 7-1, 10-inning win over the Orioles at Camden Yards. 

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Schlittler scattered three hits and one walk across 5 ¹/₃ innings of one-run ball while striking out six. 

“Man, I liked 100 miles an hour, I liked ahead in the count a lot,” manager Aaron Boone said. “I thought his stuff was again really good. Couple times he got to 3-2, seems like he won those counts where they fouled off some pitches against him. He hung around in the strike zone. If he lives in the strike zone, he’s capable of being real successful. It’s a good lineup over there.” 

Schlittler’s last time out on Tuesday in Minnesota, his outing had fallen apart in the fifth inning when he issued three of his five walks and could not make it through the frame despite entering it with a 10-1 lead. 

But the rookie right-hander was better on Sunday, especially early. He struck out the side in the first inning on 15 pitches on 98, 99 and 99 mph fastballs.

His only walk came in the fifth inning, two batters after he left a curveball up to Orioles rookie catcher Samuel Basallo, who crushed it for a solo shot. 

“Trying to work on the fastball command, trying to refine the secondary,” Schlittler said. “Little slipup in the fifth there with command, but overall, definitely a lot better than last week.” 

All six of his strikeouts came on 98 or 99 mph fastballs that were either at the top of the zone or above it, which gave the Orioles plenty of trouble. 

“The fastball up is something that plays well,” Schlittler said. “I was able to get the sinker down, played with the curveball and fastball up off that. So I was able to get really good results.” 

The Yankees still have time to figure out who will follow Max Fried and Carlos Rodón in the playoff rotation, though it seems to be coming down to a decision between Schlittler and Luis Gil.

Who the Yankees are facing will matter, as will how each of Schlittler and Gil are throwing heading into the postseason, where the ability to throw strikes and not give out free passes looms large. 

Gil will make his next start on Tuesday against the White Sox while Schlittler is currently lined up to face the Orioles again on Saturday, though the Yankees could take advantage of Monday’s day off to bump him and Rodón up a day to pitch on normal rest, which would then give them an extra day heading into the playoffs.