MESA, Ariz. -- D-backs shortstop Elvis Andrus was the first to notice something was amiss with left-handed starter Eduardo Rodriguez on Tuesday night.

After Rodriguez completed his warmup pitches for the bottom of the second inning, Andrus fielded the throw down to second from the catcher. He approached the pitcher's mound and conversed with Rodriguez before motioning to the D-backs dugout.

Out came D-backs manager Torey Lovullo and athletic trainer Ryan DiPanfilo. He examined Rodriguez and quickly determined that his night was over.

It remains to be seen how long Rodriguez will be out or if he will even have to miss any time. For now, the team is saying that he suffered left lat tightness, with the tightness coming from the part of the muscle that is more in the back than shoulder.

"I'll give you a deeper, more detailed update tomorrow," Lovullo told reporters after the game. "But for right now we're going to call it left lat tightness."

Rodriguez will be further evaluated on Wednesday. Lovullo wasn't sure whether that would include an MRI or other tests.

Rodriguez, 30, was signed in the offseason to a four-year, $80 million free agent deal by the D-backs, who are counting on him to be their No. 3 starter behind Zac Gallen and Merrill Kelly.

In his next-to-last tuneup before the start of the regular season, Rodriguez allowed one hit, holding the Cubs scoreless in the first inning before his lat tightened up prior to the start of the second. The D-backs would go on to win the contest, 4-1.

Rodriguez is expected to play a key role for the D-backs this season, so Lovullo was asked about his level of concern.

"Anytime you take a starting pitcher off the mound, there's a certain level of concern," he said. "I've been much more concerned in other situations, so I'm going to hold off and say minimal [concern] for right now. I'm going to remain optimistic. Hopefully, we'll get more information tomorrow."