PHOENIX -- It is safe to say right-hander Yoan Lopez's first professional season is off to a good start.
Cuban free agent Lopez has not given up more than three runs in any of his five starts at Double-A Mobile this year, and he has been even better recently, giving up two runs total in his last three appearances. His 1-2 record is less indicative of his work than his 2.22 ERA -- the BayBears scored six runs while he was on the mound in his four starts.
His victory came in a five-inning relief/start on May 29, when he took over in the third inning of a suspended game and pitched five innings of one-run relief.
"We like where he is," D-backs director of baseball operations De Jon Watson said. "He is getting acclimated to pitching in the U.S. and going out and competing every fifth day. The velocity has shown itself on a more consistent basis, 90-94 (mph). Some good stuff."
Lopez, 23, hit 95 mph late in spring training, one of the reasons the D-backs committed about $16 million to him in signing bonus and tax for exceeding their intentional bonus pool allowance. He has given up 22 hits and 11 walks with 20 strikeouts in 28 1/3 innings, for a 1.17 WHIP.
"The biggest thing for him is really trying to slow things down and make sure he was throwing strikes, keeping balls down in the strike zone," Watson said.
Lopez also throws a slider, a curve and a changeup, and his mission with Mobile manager Robby Hammock and pitching coach Wellington Cepeda is learning when and how to incorporate them.
"It is a mental growth process," Watson said. "Being able to throw his secondary pitches in any count, where he wants them, and really understanding when to use them, who to use them against. What information has he gathered from the hitters, especially state-side? They are different players.
"You are not seeing as many of the big free swingers as he may have seen in the past, so he really has to understand who's who. It's almost like watching (Yasmany) Tomas. Every time he gets out there, he's seeing pitchers for the very first time. Same with this kid. Every hitter he is seeing he has not seen before in his life. So you have to work your way through that."
Lopez, Hammock and Cepeda have developed a good working relationship, Watson said, and Lopez is adapting to a slightly heavier workload. In Cuba, pitchers usually started once every seven days.
"I think he is settling in, definitely," Watson said. "They said he brings it every time he goes out there. His side work has been focused and very detailed. I'm excited about his assimilation in professional baseball and how he has taken it and moved forward."
Reno (AAA, Pacific Coast)
--Peter O'Brien made his first appearance behind the plate Wednesday afternoon, when he caught the first eight innings of the Aces' 6-3 victory over Las Vegas that snapped a six-game losing streak. He also hit his eighth homer, tied for second in minor league baseball. He is slashing .367/.388/.674. O'Brien also has played two games at first base but has seen the most of his action in the outfield.
--Outfielder Tom Belza was to be promoted from Double-A Mobile, where he hit .295 with seven doubles, three homers and seven RBI in 28 games. He was tied for sixth in the Southern League with 15 runs while hitting mostly at the top of the order.
Mobile (AA, Southern)
--Right-hander Adam Miller has converted all four of his save opportunities since moving into the closer's role the last week of April, when Enrique Burgos (6 for 6 in save chances) was promoted to the D-backs. Miller's fastball has been clocked at 100 mph this season.
--Right-hander Aaron Blair has limited opponents to three earned runs or fewer in all five of his starts and is one-third of an inning short of five straight quality starts. He gave up no runs and two hits and struck out six in a May 2 start at Biloxi but did not get a decision when the bullpen could not a 1-0 lead.
Visalia (A, California)
--The Rawhide opened a six-game lead in the Cal League North with a 20-7 start. Manager J.R. House's team had a seven-game winning streak and had won 13 of their last 17. Pitching coach Gil Heredia's staff had a league-best 2.52 ERA.
--A conversion to the outfield does not appear to have affected Daniel Palka's bat. Palka has 11 doubles, two homers, 15 RBI and a .762 OPS while playing right field this season. A third-round pick out of Georgia Tech in 2013, Palka played first base primarily in his first two seasons in the system.
--Right-hander Zack Godley led the minor leagues with six victories after beating Rancho Cucamonga on Wednesday. He has a 1.25 ERA and did not give up a run in four of his first six outings.
Kane County (A, Midwest)
--Third baseman/second baseman Cody Regis, a free agent signed out of UCLA, was hitting .322 with six doubles and 11 RBI in 24 games. He was hitting .405 during a nine-game hitting streak through Wednesday.
--Stryker Trahan, catching again after playing some outfield last season, was tied for sixth in the notoriously pitcher-friendly Midwest League with three home runs through the first week of May. The D-backs' No. 1 pick out of high school in 2012, Trahan had a five-game hitting streak.
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