Still, there is reason for concern when a starting pitcher complains about tightness throughout his outing.
"My arm was tight, a little tight," Alvarez said in Spanish. "From the time I went out to the mound I felt it. From the beginning."
While the Marlins are saying it is elbow stiffness, Alvarez said it was more of his entire arm not feeling totally right. He previously felt a similar condition at San Diego on May 11. In that outing, he gave up five runs in four innings in a loss.
"He said he had a little tightness in his elbow, and he said he could pitch," Redmond said. "But we took him out for precautionary reasons.
"I think he's fine. But we'll see over the next couple days. He wanted to keep pitching, but we wanted to make sure it didn't become anything serious."
Alvarez was lifted with Miami ahead by four runs. The right-hander threw 62 pitches, 43 for strikes.
Miami's rotation already is without ace Jose Fernandez, who is out for the season after undergoing Tommy John surgery. The club has been looking for the rest of the rotation to step up, and Alvarez was doing so on Wednesday night. He lowered his ERA to 2.97.
A year ago, Alvarez missed the first two months of the season with right shoulder inflammation.
On Wednesday night, the right-hander's velocity remained steady, reaching 94 mph in the fifth inning. The final out Alvarez recorded came when he retired Anthony Rendon on a flyout to center on a 79-mph curveball.
It was an active night for Alvarez, who fielded three comeback ground balls and reached for a couple of others.
At the plate in the fifth inning, Alvarez slapped a hard grounder to third that was gloved on a diving stop by Rendon. On the play, Alvarez ran hard to first base, but he walked slowly back to the dugout.
Despite the tightness, Alvarez said he doesn't feel he needs an MRI. He also felt confident he will not have to miss a start. The Marlins will evaluate how he feels in the next couple of days.
"Yes, I'll be fine for the next start," Alvarez said. "Throughout the game, I told them I wasn't feeling well. It was a little tight."