The Angels were looking forward to having their lineup back to full strength Tuesday for the first time since the first week of the season.
It lasted one inning.
As the Angels opened a three-game series with the Houston Astros, slugger Josh Hamilton returned after nearly two months on the disabled list and Mike Trout returned after sitting ou two games because of back stiffness.
But after Trout struck out swinging in the first inning at Minute Maid Park, he left the game because of continued back problems. The Astros then rolled to a 7-2 victory and handed the Angels their fourth consecutive loss.
Trout said he was examined by a doctor before the game but would be more thoroughly evaluated Wednesday in Houston.
"He'll have some studies done," Manager Mike Scioscia said. "I'm sure he's going to have some kind of an X-ray or something.
"We'll definitely take a half-step back here and find out exactly what's going on. He can't think of one thing that he did in the course of the last three or four days that caused it."
Trout said he "didn't feel comfortable" when the game started.
"I didn't want to risk it and push it too much," Trout said. "I felt something and it's the same thing I've been feeling for a couple of days."
Asked how concerned he was, Trout replied, "Not too concerned. [I] made progress over the last two days, so it was obviously getting better, but just don't want to push it too much where it gets worse.
And in the first inning, Hamilton crushed a pitch from starter Collin McHugh more than 400 feet to the quirky, grassy incline in center field known as "Tal's Hill," where center fielder Dexter Fowler caught the ball while falling to his knees.
"Anywhere in the world he's got two home runs, except here," Scioscia said of Hamilton.
Before Hamilton was injured, he was batting .444 (12 for 27) with two home runs and six runs batted in through eight games.
Hamilton tore a ligament in his left thumb April 8 while sliding headfirst into first base in Seattle, a maneuver he chalked up to instinct.
But Hamilton returned Tuesday with a slight change of heart.