ST. PETERSBURG -- Round one goes to the Yankees. In the first battle between the top two teams in the American League East, the Yankees edged the Rays, 4-3, on Friday night at Tropicana Field, cutting Tampa Bay's lead atop the division to half a game.

But even more worrisome for the Rays was that right-hander Tyler Glasnow, who was named the AL Pitcher of the Month in April, left in the sixth inning with right forearm tightness and will be evaluated further on Saturday.

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"I don't have any update," Rays manager Kevin Cash said. "He'll go see a doctor tonight, and we'll probably have more tomorrow morning at some point.

"We noticed that he went to stretch his forearm, and that's not an ideal thing to see a pitcher do, so I'm glad we caught it, and now we just wait and see what people a lot smarter than us tell us. Other than that, I know nothing."

After Glasnow struck out Gleyber Torres on a curveball, the 6-foot-8 right-hander immediately motioned to the Rays dugout, indicating that there was something bothering him. Rays trainers came out to check on Glasnow before quickly walking off the field with the right-hander.

Glasnow, 25, said he had been feeling some tightness in the arm during the entire at-bat against Torres.

"I just felt tightness for a couple of pitches, and I felt like I should've came out of the game just because it felt tight," Glasnow said. "But yeah, just have to figure it out later."

Whenever a player, especially a pitcher, has an injury near the elbow, there's always the concern that it could be ligament damage, which could eventually force a pitcher to miss an entire season. But Glasnow said he didn't feel anything pop in the arm and will stay positive until he undergoes an MRI.

"It's not like there was pain or anything," Glasnow said. "It was just like this really strange feeling. I just thought it would be better to come out and not chance things. Feeling it for that many pitches, it was time to come out."

The sixth inning was the second time in the game that Rays trainers checked up on Glasnow. In the first inning, after he allowed an RBI single to Torres, trainer Joe Binge and Cash came out to check on the right-hander. After just one warmup pitch, Glasnow said he was fine to stay in the game.

After the game, Cash said the first checkup was just a quad issue for Glasnow and not anything related to the injury in the sixth inning.

It would be a huge blow for the Rays if Glasnow were to miss extended time. He struck out nine and allowed four runs (three earned) over 5 1/3 innings, raising his ERA to 1.86 this season, which still leads the AL.

"That was tough," said outfielder Austin Meadows, who was traded to the Rays with Glasnow from Pittsburgh last July and homered Friday in his return from the injured list. "He's leading the AL in ERA. He's been amazing out there. Seeing him go down, hopefully it's nothing serious. That's a tough blow."

If Glasnow misses time, he would join Mike Zunino, Michael Perez, Matt Duffy and Joey Wendle as key contributors who are on the injured list.

"It's frustrating," Cash said. "But you know, you have to find a way. This is where we talk about our depth all the time. Our depth will be challenged and tested, and we have confidence in the guys and the options that we have."

Missed opportunity on Friday
With the Rays trailing, 4-3, in the seventh inning, Tampa Bay had a key opportunity to tie the game, but was unable to score in a bases-loaded nobody-out situation for the second consecutive game.

Yankees reliever Adam Ottavino struck out Tommy Pham on a 3-2 slider out of the zone, and infielder DJ LeMahieu turned a 1-4-3 double play to retire the side.

"There were a couple of missed opportunities in there," Cash said. "That was frustrating because we felt like we had them on the ropes a little bit, bases loaded, no outs. We just couldn't come up with the big separator there."