I’m not sure when it began. It was some time after Ichiro joined the front office as Special Assistant to the Chairman. We all noticed Ichiro racing out from the clubhouse after a Mariners victory from the very beginning. But what began as a race to get to the front of the line of high fives quickly morphed into something else. At some point during the season, when he reached the top of the mound, Ichiro started bringing his arms to his chest, then lift his right leg up, and pause in a rough imitation of the balance point in Marco Gonzales’s windup. What probably began as one teammate ribbing another continued throughout the rest of the season, morphing into something else entirely. I think Ichiro, in his own weird way, was reminding Marco of a word that defined his 2018 season: balance.

Last year was his first full season after undergoing Tommy John surgery back in 2016. All he did was quietly rack up 3.6 fWAR while posting a FIP 17% better than league average and the fifth-best walk rate among qualified starters. He was the second-most valuable pitcher on the Mariners and the tenth-most valuable pitcher in the American League. Even the most ardent Gonzales supporters could not have predicted such a successful season.

His breakout was fueled by significant changes to his pitch repertoire. As a prospect working through the Cardinals organization, his excellent changeup was his calling card. When the Mariners acquired him in 2017, his change piece was still the foundation of his repertoire. But something happened during the offseason prior to 2018. Gonzales discovered (or rediscovered) a cut fastball, giving him a fifth pitch to mix into his arsenal. First introduced as a way to combat right-handed batters, Gonzales wound up throwing his cutter more frequently than of any of his other pitches by the end of the year.

But it wasn’t just his cutter that helped him break out, Gonzales’s return to health also helped him regain his feel for his curveball too. Here’s what he told David Laurila during spring training: “My curveball was probably hurt the most by the layoff. I still had good spin, but being able to command it where I wanted to was out of the question.” It quickly became his best pitch, racking up swinging strikes while also keeping the ball on the ground when contact was made. Opposing batters managed a .289 wOBA and just a .095 ISO off his breaker.

With five pitches in his arsenal, three of which were secondary pitches, you’d expect a pitch mix that leaned on one or two of them with the other pitches simply complementary. Instead, Gonzales bucked convention and found a perfect balance between all of his pitches.

As the season progressed, Gonzales began throwing his sinker, changeup, curveball, and cutter at almost the same frequency. Against left-handed batters, his changeup would be replaced by a few more four-seam fastballs, but the foundation of his arsenal was evenly divided between those four pitches. That kind of balance is a testimony to his confidence and feel for each of those pitches. His entire repertoire was at his disposal whenever he wanted, creating a nightmare for opposing batters.

In any given count, an opposing batter had four different pitches to deal with. That lack of any overt tendencies when ahead in the count or behind in the count gave Gonzales a huge advantage. By balancing his pitch mix, he forced opposing batters to keep all of his pitches in mind, avoiding situations where batters could hone in on a particular pitch type.

If he felt like he was 90% healthy in 2018, this season could see another big step forward for Gonzales. He’s another year removed from his surgery and has a very successful season under his belt. Rather than focusing on returning to strength, he can focus on building consistency this offseason. Or as he puts it, “balance his routine” to focus on both strength and durability.

There’s that word again. Greater strength and durability should help him avoid the loss of velocity he suffered during the summer last season. And with confidence in his entire repertoire and a balanced plan of attack, Gonzales is poised to ascend to the top of the Mariners starting rotation. That’s not simply because of the James Paxton-sized hole atop the rotation. Gonzales raised his potential ceiling in a significant way last season and has cemented himself as a important piece for the Mariners future.