GOODYEAR, Ariz. -- Logan Gilbert couldn’t contact his coaches about the ongoing changes he was making to his pitch grips this offseason, which he hoped would lead to more distinct shapes on his breaking balls and, in turn, more missed bats. But despite the lockout prohibiting conversations with Mariners officials, he did come across a well-versed consultant who offered a few insights.

Jacob deGrom.

The pitching powwow between Gilbert and the two-time National League Cy Young Award winner took place at their alma mater, Stetson University in DeLand, Fla., where the Mariners’ towering right-hander threw a bullpen session once per week in the offseason. On some of those days, deGrom was training there, too, with his Mets battery mate Patrick Mazeika, who also went to Stetson.

“I was just trying to learn as much as possible,” Gilbert said. “He just kind of goes about his business, and it’s effortless for him, but I would just try to watch and see what he does. I know we throw a little different body-movement wise, all that kind of stuff, but it's good to learn from him.”

So what did he learn?

“He throws everything glove-side,” Gilbert said. “That's a focus for him. I'm trying to incorporate that more in practice in bullpens. So I feel like that's helps. ... We're both on the first-base side [of the rubber], so everything is in the glove-side lane, which is the hardest thing to do with the extension out front. So if you do that, you can go to any side of the plate.”

The changes Gilbert set out to make were in progress well before he connected with deGrom, dating back to late last season, but after that promising rookie year, it was validating to hear from arguably the greatest pitcher of his generation.

Specifically, Gilbert set out to create a firmer slider than the more sweeping one he threw last year, and he’s also throwing a harder curveball, the pitch that his Minor League scouting reports raved about -- but one that he admittedly didn’t have a great feel for last year.

“The priority is just the location and the accuracy,” Gilbert said, "and then I also changed the movement to kind of tailor to that. So for instance, with the slider, I'm throwing it harder and shorter, but I feel like it's really tight, so I can control it better.”

Gilbert’s new-look arsenal was as impressive as advertised during his Cactus League debut on Thursday, kick-starting a 3-2 win over Cleveland. Gilbert struck out six of the 11 Guardians he faced over three innings, and he allowed just one hit: a mistake-pitch homer to Daniel Johnson in the second inning. When he’s going right, with his revamped repertoire, his curveball is around 82-83 mph and his changeup at 85-86 mph.

The huge uptick in velocity came most noticeably in Gilbert's slider, which was at 89 mph after sitting in the low-80s last year. Only four qualified starters threw a slider that hard last year on average, with deGrom leading the pack.

“The slider, I'd like to think, is kind of off of what he does,” Gilbert said. “Not to say it's the same pitch, but I'm trying to get there just messing around with different things. We had plenty of time this offseason, so I just tried to figure it out.”

Said Mariners manager Scott Servais said following Thursday’s game: “That's as good as I've ever seen his breaking pitches.”

The logic behind Gilbert’s changes was to help the secondary stuff better play off his fastball, which is arguably the best on Seattle’s starting staff. But he threw it so regularly -- almost exclusively the first time through the order, and for 61.5% of his total pitch usage -- that it became predictable. Gilbert’s fastball averaged 95.3 mph and consistently reached the high-90s, but he generated whiffs on just 21.6% of them, per Statcast, and opponents hit .254 and slugged .401 against it. The new slider tunnels better and looks like a fastball out of hand.

“I really want [the slider] to play off the fastball the best, because teams know I throw my fastball a lot,” Gilbert said. “And I think that there are some good ones today that probably looked like a fastball until the last second. That's the idea.”

At times last year, Gilbert flashed arguably the best pure stuff on the staff, and at others, he stumbled amid expected challenges as a rookie. In 24 starts, he compiled a 4.68 ERA and had 128 strikeouts and 28 walks in 119 1/3 innings.

With a revamped arsenal, he and the club expect things only to go up from here.