PEORIA, Ariz. -- Until Cactus League games begin on Friday, it's hard to judge exactly how well pitchers are throwing. But that hasn't stopped young closer Edwin Diaz from opening eyes in Mariners camp.
Diaz racked up 34 saves last year with a 3.27 ERA and one of the highest strikeout ratios in the American League, but at 23, he's still learning and growing. And with some extra strength on his wiry 6-foot-3 frame and no World Baseball Classic interrupting his spring, he's looked imposing in the early work at the Peoria Sports Complex.
:: Spring Training coverage presented by Camping World ::
"Edwin Diaz's first few bullpens have been electric," general manager Jerry Dipoto said Wednesday on his latest Wheelhouse Podcast. "He's not the only one. There's a handful of guys that have looked awesome in the early going, and maybe no one more so than Eddie."
Spring Training:Info | Tickets | Schedule | Gear
Dipoto noted that Diaz has latched on to veteran Juan Nicasio, Seattle's biggest free-agent addition, and the two have been doing "towel work" each morning before the team gathers for meetings to fine-tune the ability to repeat his throwing motion.
"When Edwin gets in his funks, it's usually relative to not repeating his release point and delivery," Dipoto said. "This spring, it's been remarkably consistent. As a result, he has his usual explosive velocity and fastball, and his slider has been incredibly consistent through the first two bullpens, which was not the case in last year's Spring Training.
"This year, it looks spot-on, and his command is great. And he's actually working on a changeup. It's a pretty firm changeup. I guess when you're throwing 100, your changeup does look firm. But the ball sinks, and it could be something in his back pocket that he can introduce against an occasional lefty."
• Subscribe to The Wheelhouse podcast

Diaz, who threw a sizzling session of live batting practice on Wednesday, isn't the only pitcher who has caught Dipoto's attention.
"Guys like Max Povse," he said. "Rob Whalen looks so much better than he did a year ago, in both physical and his mental approach on the mound. Art Warren was really a standout in the early sessions and caught a lot of the interest of our staff. A young guy we picked up as a Minor League free agent, Johendi Jiminian, is a big, big arm and might be as hard a thrower as we have in camp. He's been interesting to watch in the early going."
And, yeah, one of the "old" guys has been impressive to the GM in the initial days as well. The Mariners are counting on Felix Hernandez to bounce back from an injury-plagued campaign, and he's come to camp with a bit of an edge.
"Felix looks energized," Dipoto said. "He's excited to be a part of it, and I feel like Felix is engaged in the work day in a way I haven't seen in a couple of years. And if I've seen anything that excites me most, that's it."
Worth noting
• Outfielder Junior Lake was on the field for the first time after his Minor League deal with a camp invite was finalized. Lake, 27, has played parts of four seasons in the Majors and spent last year in Mexico and with Boston's Triple-A affiliate.
• Right-handed reliever Ryan Garton, who has been held back from throwing as he returns from hip labrum surgery, is scheduled to throw his first bullpen session on Tuesday.
• Dee Gordon is wasting no opportunities to get comfortable in the outfield. While teammates where taking batting practice and a number of Peoria-area volunteers shagged balls, Gordon ambled out to center field and spent about 15 minutes chasing down deep drives and making several nice sliding catches.
• James Paxton was among the group throwing live batting practice for the first time Wednesday as he continued gearing up for his Cactus League debut on Tuesday.