ST. PETERSBURG -- Tuesday night was wildly frustrating for the Rays, but apparently it could have been worse.

They lost to the Astros, 5-0, falling two games behind the Blue Jays in the American League Wild Card race. Their lineup was no-hit into the fifth inning and shut out for the second straight night at Tropicana Field, their first back-to-back shutouts since Aug. 11-12, 2017. And ace Shane McClanahan walked off the mound with a trainer during a plate appearance in the fifth inning of his second start back from the 15-day injured list.

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The last point would seem to be the biggest concern, but McClanahan eased some potential worries afterward. The All-Star left-hander was removed due to tightness/spasms in the left side of his neck, not a recurrence of the left shoulder injury that sent him to the IL, and he believes he’ll be ready to make his next scheduled start.

“I fought to stay in the game. I feel fine now. I felt fine five seconds after,” McClanahan said. “But [in the] middle of September, I respect the precautionary move. … I'm ready to get back out there and help this team win.”

McClanahan walked Jose Altuve to begin the fifth, then threw three straight balls below the strike zone to Astros shortstop Jeremy Peña. McClanahan appeared to grimace and twist his neck after throwing a changeup during that sequence, which drew manager Kevin Cash and first assistant athletic trainer Mike Sandoval from the home dugout to the mound.

McClanahan appeared to tell Cash, “I’m good,” on the mound, but he left alongside Sandoval after a brief conversation. As Cash noted afterward, “I’d rather be proactive than not.” McClanahan was replaced by right-hander Shawn Armstrong, who went on to walk Peña.

“He was pretty adamant he did not want to come out. He was not happy about that. But we're trying to make the best decision,” Cash said. “It's the second start back from missing some time on the IL. I think we all understand how important he is to our club.”

And, in light of recent events, why the Rays would be so cautious.

McClanahan was scratched from his Aug. 30 start in Miami only minutes before he was scheduled to pitch and landed on the injured list the next day due to a left shoulder impingement. He served the minimum 15-day stint, returned to the mound last Thursday in Toronto, pitched like he was at full strength and said Monday he felt “normal.”

After leaving Tuesday’s game, McClanahan did not immediately return to the Rays’ clubhouse for treatment, as obvious an indication as any that he wasn’t overly concerned about his status moving forward. Instead, he stood next to pitching coach Kyle Snyder as the inning continued.

“Just a little tweak, whatever you want to call it. Tried stretching it out, felt fine,” McClanahan said. “They saw it and [exercised] the abundance of caution, but I think it was the right move.”

Before that, catcher Francisco Mejía noted McClanahan was “trying to find his command” as he allowed four runs in his first three innings against the Astros. The All-Star starter has thrown 67 percent of his pitches for strikes this season, but only 45 of his 80 pitches were strikes on Tuesday. and he walked a career-high four batters. He was charged with a career-high-tying five runs overall, including one Armstrong allowed to score in the fifth.

McClanahan induced only two swinging strikes on 19 swings during his first trip through Houston’s lineup and five whiffs on 52 pitches during his first three innings. He seemed to bounce back in the fourth, recording three strikeouts around a one-out walk, then left after throwing 10 pitches in the fifth.

“Obviously I'm frustrated. Middle of September, we're in a playoff push, I need to be better than that,” McClanahan said. “I could have done a way better job tonight executing pitches, throwing quality strikes and limiting the damage.”

McClanahan would have had to be nearly perfect, though, given the way Houston has stifled Tampa Bay’s lineup. The Rays’ first hit was Christian Bethancourt’s two-out single in the fifth, and they didn’t get a runner to third until they loaded the bases with one out in the ninth. Ryan Pressly shut down that rally, however, extending the Rays’ scoreless streak to 20 innings.

“We just couldn't get the final hit. Those are things that will happen in baseball,” Bethancourt said. “We're facing a great pitching staff. We've got to make some adjustments.”