SCOTTSDALE, Ariz. -- D-backs right fielder Kole Calhoun will undergo surgery on his right knee Wednesday morning after an MRI on Tuesday showed a medial meniscus tear.

The procedure is known as a partial medial meniscectomy.

D-backs manager Torey Lovullo said Calhoun told the team that he had experienced some discomfort in the knee beginning in the offseason.

Lovullo declined to say how long Calhoun would be out, preferring to wait until after the procedure to hear what the medical team determines. Players who have had similar injuries have typically missed at least four to six weeks.

"Anytime one of your best players needs to step away to have a procedure, I'm concerned about him as a person, first and foremost and then, obviously, how he fits into this team," Lovullo said. "And he is such an important part of this team."

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While they were waiting for the results of Calhoun's MRI to come back, Lovullo and his staff discussed the team's options for replacing him in right field.

Among the candidates are Pavin Smith, Daulton Varsho, Tim Locastro, Trayce Thompson, Wyatt Mathisen, Josh VanMeter, Andy Young and Josh Rojas.

"It's an opportunity for somebody else to step up," Lovullo said. "We have the ‘next man up’ mentality here, and we've got some good players who are going to get some opportunities. So I'm obviously concerned. I don't want to sugarcoat that. But I know it's going give an opportunity to some other guys, and I'm excited about that, as well."

Rough opener for Smith
Left-hander Caleb Smith had a rough go of it in his first start of the spring. He allowed six runs on four hits while walking two in two innings in the D-backs’ 7-2 loss to the Padres on Tuesday at Salt River Fields.

"I felt all right," Smith said. "Command could have been better. Obviously, the two walks, both of those guys scored. You got to cut down on the walks and just put guys away whenever I have two strikes. And I wasn't able to do that."

The big blow of the game came in the second inning, when Fernando Tatis Jr. hit a grand slam to left field.

While it's just the first outing of the spring, Smith is a competitor and wasn't pleased with what the final line looked like.

"I mean, you never want to do that," Smith said. "There's positives to take away from this. … I learned don't throw Tatis a fastball. I mean, yeah, it happens. Just glad it's Spring Training and we got it out of the way early."

Mathisen, Young moving around
With the D-backs looking for a bench player who hits from the right side, as well as a potential replacement for Calhoun in right, Mathisen and Young are going to see some time at a variety of spots this spring to see how they handle them.

Mathisen played third base in seven games for the D-backs last year. In Tuesday's game, he played first base, a position at which he logged 72 games in the Minors. You will also see him get some time this spring at both outfield corners.

That's more of a stretch than the infield for Mathisen. He has played just one inning in the outfield over his professional career.

Young, meanwhile, is an infielder by trade and can play all four infield spots. He played left field Monday and allowed a ball to roll through his legs to the wall. He has played 10 games in the outfield as a professional.

"We just want to give guys some versatility, give them a different look and a different reason to get in the lineup," Lovullo said.

Nice one for A.Y.
Alex Young looked good in his first spring outing, tossing two scoreless innings while allowing a hit and striking out one.

The left-hander's most likely route to the Opening Day roster is through a bullpen spot, but he's being stretched out as a starter early in camp and it's not out of the question that he could pitch his way into the rotation mix.

Up next
The D-backs travel to Goodyear Ballpark to take on Cleveland on Wednesday at 1:05 MST. Luke Weaver will get the start for the D-backs. Others scheduled to pitch include right-handers Taylor Widener, Corbin Martin, Chris Devenski and Yoan López along with lefty Tyler Gilbert.

Zach Plesac will start for Cleveland.