Another pitching prospect's debut on deck for D-backs

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SAN DIEGO -- The D-backs could give another one of their young pitching prospects a look on Monday. Indications are pointing towards 23-year-old Triple-A Reno right-hander Yilber Diaz -- Arizona's No. 16 prospect, according to MLB Pipeline -- getting the start against the Braves.

With left-hander Jordan Montgomery out until after the All-Star break amid his stint on the 15-day IL due to right knee inflammation, the D-backs gave 21-year-old Cristian Mena a look by starting him against the Dodgers on Wednesday night in Los Angeles.

Mena, the D-backs' No. 11 prospect, had a rough first inning, when he allowed four runs, including homers by Freddie Freeman and Teoscar Hernández. But Mena tossed two scoreless innings afterwards, before being removed at 70 pitches.

Following the game, Mena was optioned back to Reno, but he did make an impression.

“He was fine,” D-backs GM Mike Hazen said of Mena. “I thought he did a really good job of recovering after the first inning. It wasn’t a one-and-done, but we'll play with the spot [in the rotation] a little bit. We'll see how it goes. You know, Monty’s [return], I'm very hopeful is not going to be too long after the All-Star break. So if that's the case, then the spot has two more turns through, and then we'll see where we go from there.”

Diaz began the season with Double-A Amarillo, posting a 4.33 ERA in 11 starts. He struck out a whopping 77 batters in 54 innings and was promoted to Reno on June 11.

With the Aces, Diaz has a 3.27 ERA in four starts and has struck out 28 batters in 22 innings.

“He's got good stuff,” Hazen said. “Obviously, the fastball is pretty electric. He’s got a good slider, good curveball, so you know he's made some steady progress from Double-A to Triple-A

Upgrading the rotation and building depth in it was a priority for the D-backs during the offseason, and they thought they were in good shape after signing free agents Eduardo Rodriguez (four-year deal) and Montgomery (one-year deal) to team with Zac Gallen, Merrill Kelly and Brandon Pfaadt.

Injuries, however, have decimated Arizona and left it scrambling to fill rotation spots.

First, it was Rodriguez who went down. He strained his left lat muscle during Spring Training and re-injured himself trying to come back too soon, so he has not thrown a regular season pitch for Arizona yet.

Kelly also has missed time due to injury. He went on the 15-day IL with a right shoulder strain on April 23 and was transferred to the 60-day IL on May 2. Montgomery, who signed with the D-backs on March 29, made two starts with Reno, and after making 13 starts with Arizona, he went on the IL with right knee inflammation.

The D-backs have dipped into their young pitching depth with Ryne Nelson, Slade Cecconi, Tommy Henry and Blake Walston.

Henry struggled (7.04 ERA in nine appearances, including seven starts) and was optioned back to Reno on June 23, and Walston suffered left elbow inflammation and was placed on the 15-day IL on June 6.

That left the D-backs willing to give an opportunity to Mena, and likely Diaz, sooner than they expected.