ST. PETERSBURG -- Hard-throwing rookie right-hander Edwin Diaz continued to shine in his new relief role with the Mariners, throwing 2 2/3 scoreless innings after replacing injured starter Taijuan Walker in the fourth inning of Tuesday's 8-7 loss to the Rays.The 22-year-old Puerto Rican is in just his second week
ST. PETERSBURG -- Hard-throwing rookie right-hander Edwin Diaz continued to shine in his new relief role with the Mariners, throwing 2 2/3 scoreless innings after replacing injured starter Taijuan Walker in the fourth inning of Tuesday's 8-7 loss to the Rays.
The 22-year-old Puerto Rican is in just his second week in the Majors, but he's made a quick mark with his electric arm and a fastball that touched 99 mph after he heated up in his 32-pitch outing.
Diaz allowed just two singles and struck out five in his longest stint yet. He's posted a 1.69 ERA with one earned run in 5 1/3 innings, allowing four hits with eight strikeouts and two walks in his new gig after a rapid rise from Double-A Jackson following his conversion to the bullpen.
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"Edwin threw the ball really well," manager Scott Servais said. "He was very aggressive, and it was the right spot for him to come in the game and keep it tight. He really managed a very efficient pitch count, so we were able to get him to turn the ball over in the seventh, which was key at that point. When we did, I thought we were in great shape."
Diaz was in line for his first Major League win until the Rays rallied from a 7-4 deficit by scoring four runs in the seventh off Nick Vincent and Mike Montgomery.
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But despite the loss, the youngster again showed that he could be a much-needed weapon as a power right-hander in a bullpen that has been trying to keep things pieced together. Diaz is learning the role of a reliever, and getting thrown into a game as an injury replacement was a new situation.
"It was a tough situation, my first time doing that, but I tried to make my pitches and get outs," Diaz said. "I felt good. When I came out, everybody told me [to] take my time. I started warming up nice and easy, and my arm felt good. I threw maybe 20-25 [warmup] pitches and when I felt good, I started pitching."
Diaz struck out four of the last five batters he faced, so clearly the multiple-inning situation didn't faze him.
"When we first sent him out there, I was thinking 35-40 pitches," Servais said. "He has started and had some longer outings. He's used to being a starter. That didn't bother him at all. It was a tough spot to throw a young pitcher in there, but he got warmed up on the mound and handled it great."
For Diaz, the Mariners' top-rated pitching prospect, it was another step forward in his rapid development.
"I feel good. I feel happy," he said. "Everybody treats me like another guy here. They help me a lot, teach me a lot of things. I'm very happy to be here."
Greg Johns has covered the Mariners since 1997, and for MLB.com since 2011. Follow him on Twitter [
@GregJohnsMLB]() and listen to his podcast.