ARLINGTON -- Justin Steele stayed with the play and recorded an impressive out, but it came at a cost for the Cubs’ Opening Day starter. The North Siders will now hope that the sight of the left-hander clutching the back of his left leg on Thursday night does not prove overly costly for the rotation as this season gets underway.

During the fifth inning of a 4-3 loss in Texas that lasted 10 frames, Steele tumbled to the ground at Globe Life Field and grabbed at his left hamstring after fielding a bunt off the bat of Rangers outfielder Leody Taveras. It brought a swift end to Steele’s night and subdued the feelgood vibes that come with shifting from Spring Training to Opening Day.

“You're going to have things like this happen during the season,” Cubs manager Craig Counsell said. “First day of the season, it probably stings a little worse. But this is going to be part of our season and it's testing us immediately.”

This first test is likely to include Steele landing on the 15-day injured list, as Counsell detailed in the wake of the walk-off loss to the reigning World Series champions. The manager noted that Steele sustained a left hamstring strain and would undergo imaging on Friday’s off-day to gather more information.

It is a blow to a rotation that is already without veteran righty Jameson Taillon, who is on the 15-day IL and working his way back from a back issue that flared early in the spring. Backup rotation options on the 40-man roster include Triple-A Iowa righties Hayden Wesneski and Ben Brown. Lefty Drew Smyly is also an option to move back out of the bullpen.

“We're going to rely on depth this year, for sure,” Cubs president of baseball operations Jed Hoyer said before Thursday’s game. “There's no question we'll need a lot of pitching. And I think we're in good shape that way organizationally. But that's one of the daunting aspects of starting this marathon.”

Steele had six strikeouts through his 4 2/3 innings, with his lone setback a sacrifice fly off the bat of rookie Wyatt Langford in the fourth. In the fifth, the lefty allowed a leadoff double to Ezequiel Duran, who was then erased during a rundown between second and third. Evan Carter reached first safely after his fielder’s choice groundout on that play.

That set things up for Taveras, who bunted a pitch up the first-base line to advance Carter with the score caught in a 1-1 deadlock. Steele hustled off the hill, reached down to pluck the ball from the ground and made a bare-handed flip to first baseman Michael Busch for the out. The pitcher immediately grabbed his leg after falling.

“When I was leaning over backhanding the ball, I just kind of felt something grab,” Steele said. “So I just went down with it and didn't want to do anything to risk further injury.”

What was Counsell thinking as he headed out to check on Steele?

“It's just a shame,” said the manager. “I mean, he's pitching really, really well. Obviously he's an important member of the team, and it looks like we're going to miss him for a little bit here.”

In his final spring start on Friday, Steele left his appearance against the Giants after being struck on the left knee by a sharp comebacker. The pitcher sustained a left knee contusion, but showed quick improvement and was cleared to continue on course for his Opening Day assignment.

The Cubs entered this season with high hopes for Steele, who enjoyed a breakout showing last year. The lefty won 16 games and piled up 176 strikeouts against 36 walks, with a 3.06 ERA in 173 1/3 innings. Steele was named to his first All-Star team and finished fifth in voting for the National League Cy Young Award.

“He was awesome for us last year,” Cubs outfielder Ian Happ said. “You watch him pitch and see how much he cares, but it's not talked enough just about how much he cares about the rest of the group, how much he invests himself into individuals.”

Steele hopes he's not sidelined for too long.

“Spirits are high,” he said. “Opening Day, all the jitters and everything, I was definitely nervous today leading up to the outing. It was good to feel all those emotions and get back out there, get on the horse again. I'll have a speedy recovery from this and get right back out there.”