NEW YORK -- Rays ace Shane McClanahan was obviously frustrated with his performance after allowing five runs in the third inning and seeing Tampa Bay’s three-game winning streak end in a 7-2 loss to the Yankees on Wednesday night at Yankee Stadium.

But a cause for greater concern came after the game, when it was revealed that McClanahan experienced some tightness on the outside of his left forearm in his fourth and final inning against the Yankees. That concern was only amplified when McClanahan was placed on the 15-day injured list after flying back to Tampa, Fla., for further evaluation and imaging on Thursday’s off-day.

The club announced McClanahan’s placement on the IL on Thursday night without specifying an injury but added, “The Rays are in the process of gathering further information and updates will be provided when available.”

“You don't want to see anybody on the team have to go anywhere to get anything checked. Mac is obviously extremely important to our team,” said outfielder Luke Raley, who left Wednesday’s game due to a right knee contusion.

McClanahan said Wednesday night that the outside of his forearm “just kind of got tight, kind of grabbed on me a little bit” as he was warming up before the fourth. He threw 18 pitches and completed a clean inning, then informed manager Kevin Cash when he returned to the dugout.

“It just grabbed and wouldn't let go, and I was like, ‘This is kind of interesting,’” McClanahan said. “I got through the fourth and made note of it to him. I told him, I said, 'Hey, listen, this happened. I can keep going.’ And obviously, we decided to err on the side of caution.

“I'm not going to speculate. I'm not going to make any assumptions. We're just going to take it day by day and see what comes up.”

Despite his final line and eventual placement on the IL, McClanahan didn’t show signs of a possible injury. His fastball averaged 97.3 mph and maxed out at 99.8, and his velocity was up on everything he threw. Cash said McClanahan likely wouldn’t have returned to pitch the fifth even if he hadn’t mentioned the tightness in his forearm, as he had thrown 82 pitches in four innings.

It has been a frustrating stretch for McClanahan, the 26-year-old two-time All-Star who pitched like the American League Cy Young Award frontrunner for the season’s first 2 1/2 months. He had two outings cut short by mid-back tightness before going on the 15-day IL on July 1. He has completed six innings only once since then, and he has allowed a career-high-tying five runs in two of his past three appearances.

The All-Star left-hander has given up an early lead in three of his past four starts since returning from a stint on the injured list due to a mid-back issue. He hasn’t earned a victory since June 16, going winless with a 7.36 ERA in six outings during that stretch. After the Rays won each of his first eight starts and 13 of 15 to begin the season, Tampa Bay has lost four of its past six games behind the Opening Day starter.

“The last few outings have been pretty uncharacteristic of myself, and it's one of those times in my career where you either put your head down and hide or you just keep your chest up, keep working and trust it all sorts itself out,” he said. “I'm just going to keep working and just move on. That's all I can do.”

Wander Franco continued a strong road trip, giving McClanahan a two-run lead with a two-run shot to right field off Yankees ace Gerrit Cole in the first inning that sailed a Statcast-projected 431 feet, the longest homer of his young career. McClanahan then cruised through the first two innings on 28 pitches, retiring all six batters he faced.

While Cole locked in and put together a seven-inning, eight-strikeout start, McClanahan fell behind in the count a few times in a 36-pitch third. When he fired fastballs in the strike zone, the Yankees made him pay.

Harrison Bader hit a fastball to left field for a leadoff double, then Anthony Volpe smacked a 2-2 fastball out to right field for a tying two-run shot that, according to Statcast, would have been a homer in only two Major League parks: Minute Maid Park and Yankee Stadium.

Isiah Kiner-Falefa hit a 3-1 fastball to right for a one-out single, and Gleyber Torres kept the inning alive with a two-out base hit. That brought up Giancarlo Stanton, who crushed a 3-1 fastball a Statcast-projected 408 feet to right-center for a tiebreaking three-run homer.

“I credit them,” Cash said. “I mean, they hit him in some fastball counts. The 3-1 fastball to Stanton, he was ready for it. Most hitters are probably looking for something hard in that count, and he got it and then he barreled it.”