PEORIA, Ariz. -- He flashed that megawatt smile when talking about the eager energy in Mariners camp among his many early-arriving peers, but that grin rapidly abated when Julio Rodríguez began a blunt self assessment to his individual performance in 2023.

“You heard about it -- I wasn't happy with it,” Rodríguez said, before going on a full-course, two-minute tangent for one final reflection of last season before turning to ‘24.

“There were a lot of moments that I feel like I should have done better, like I could have done better,” Rodríguez said. “I know my ability. I know what I want for myself. I know a lot of people are going to say, 'Oh, like he's struggled on this. He struggled on that.' But none of you guys -- with respect to all of you guys and everybody that watched me, everybody that supports me -- none of you guys would want me to be successful for this team like I want to be successful for this team.”

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They were stern words for a player who finished fourth in the American League MVP Award voting, became just the 44th player in AL/NL history with a 30-30 season (and only the fourth age-22 or younger) and was on a historic hot streak in August, at one point tallying a record 17 hits in a four-game span.

But falling short of the playoffs on the season’s penultimate day -- and perhaps more so, the stark ebbs and flows with his individual production earlier in the year -- left him embittered.

“I want to win with this team,” Rodríguez said. “I want to do the best that I can to be able to win with this team. I know people will get frustrated, but I know nobody is going to get as frustrated as I [was] once I kind of failed. The only thing I can do is learn from it, grow from it, work on it and come back here and get better.”

For all of his charismatic flair, which is a large reason he’s blossomed into one of MLB’s most prominent players -- he also carries a fiery edge that at times reveals an emotional competitor.

"Julio has done a really good job of sitting back and assessing,” Mariners manager Scott Servais said. “'This is how I trained going into last year, OK, this is how my season played out.' And he's admitted, he had one really good hot streak, a month, month and a half, and it was an unbelievably awesome streak. But other than that, there were inconsistencies there in his game.”

Rodríguez was the best player in the game in August, when the Mariners -- not coincidentally -- set a franchise record for wins in a single month, but until that point, he was -- admittedly -- too regularly making poor swing decisions, which often made him a liability in high-stakes situations.

According to FanGraphs, in high-leverage moments between Opening Day and the Trade Deadline, Rodríguez slashed .167/.327/.286 (.613 OPS) and was worth 80 wRC+ (league average is 100). But from August on, those numbers were .375/.464/.750 (1.214 OPS) and 218 wRC+, respectively.

In late and close games, a separate but similar criteria, he slashed 226/.328/.340 (.668 OPS) in the first four months, then .360/.448/.480 (.928 OPS) in the final two months.

“For me, that was a sophomore slump that I was grateful for, that I was able to learn from, that I know it's going to help me out down the road in my career,” Rodríguez said. “And that's something that I'm not going to take for granted. And that's something that I will never forget. It's always going to keep pushing me to keep getting better to never feel that way again.”

Two years ago, Rodríguez reported here as a precocious prospect eager to play his way onto the Opening Day roster. Last year, he’d just won the AL Rookie of the Year Award, was headed to the World Baseball Classic and had rapidly risen to superstardom.

And while there was always deliberation and intent behind his preparation, it appears to have risen to new heights this spring.