CHICAGO — As reliever Dan Altavilla blew through three Chicago White Sox batters Saturday in his major-league debut, the least surprised person at U.S. Cellular Field might have been his former Double-A Jackson teammate.
“His stuff is amazing,” Mariners closer Edwin Diaz gushed. “You saw it (Saturday). They made him a reliever in spring training before me, and he’s gotten better and better. Now he’s got the chance to be here.”
The Mariners converted Diaz and Altavilla to relievers this season in the belief that their stuff would spike upward by trimming their repertoire to two pitches: a fastball and a slider.
Club officials put Diaz, their most-advanced rotation prospect, on a fast track after moving him to the bullpen in early May. He made just 10 relief outings, during which he allowed no earned runs, before gaining a June 4 promotion to the big leagues.
By Aug. 2, he was the Mariners’ closer and entered Sunday with 11 saves in 11 chances while compiling a 2.15 ERA in 36 appearances and striking out 69 batters in 37 2/3 innings.
But at Jackson, Altavilla was the closer — even as Diaz was learning the ropes. Altavilla made the switch in spring training and unlike Diaz, had previous experience as a reliever.
“I closed in college,” Altavilla said, “so I was very familiar with it. I don’t think it’s that big of a transition. But it was definitely a little different at first, getting comfortable at coming out of the pen in big situations with guys on base.”
More than comfortable, judging from the numbers. Altavilla compiled a 1.91 ERA in 43 games at Jackson with 16 saves in 20 chances. He also kept a close watch on Diaz’s big-league efforts.
“I keep updated with him every night,” Altavilla said. “I’d check the box score. If a guy has it on video in the clubhouse, I’ll watch him. Edwin is definitely a special guy. I saw what he could do in Double-A, and I kind of molded my game after him.
“I just took it from there and stayed positive throughout the journey. And now I’m here.”
Manager Scott Servais cautioned early Saturday against judging Altavilla against Diaz’s performance but seemed to soften that view, at least a little, after watching Altavilla’s impressive nine-pitch debut, during which he hit 100 mph on the radar gun.
“Electric stuff,” Servais said. “I don’t know what they’re drinking down there in Tennessee, but they throw pretty hard. Glad to get that one out of the way for him. We’ll see where he fits in our bullpen going forward.”
Altavilla pitched again Sunday and retired both batters he faced, including one on a strikeout.
Diaz said he saw the same guy he saw in Jackson while noting one key difference:
“He proved (Saturday) in that inning that he can pitch here,” Diaz said.