2017 Renfroe vs. LHP: .316/.392/.684, 184 OPS+ 2017 Goldschmidt vs. LHP: .311/.422/.591, 171 OPS+
Of course, Renfroe is not Goldschmidt. He batted just .202/.244/.393 against right-handers last season, and those numbers suggest a player who might be better served in a platoon situation. That's not exactly what the Padres envisioned for a former first-round pick and one-time top prospect.
The Padres aren't willing to confine Renfroe to a platoon role just yet, and he spent the offseason working on drills designed to help him counter right-handed pitching. He started slowly against righties this spring, but in the Padres' 10-4 Cactus League victory over Oakland on Saturday, Renfroe scorched a first-inning single and a seventh-inning homer -- both against right-handers. (He's 2-for-6 with a double and a homer against lefties.)
"I've had great at-bats against righties this Spring Training, so that's all I care about, honestly," Renfroe said. "I'm just working on getting my swing back. I'm not worried about whether I can hit righties or whether I can hit lefties. I just go out there and do my thing."
If the Padres were to platoon Renfroe, he'd be one of the best righty-hitting platoon options in recent memory.
The above graph looks at all 193 hitters who recorded at least 100 at-bats against left-handed pitching last season. Below the trendline, Renfroe is probably the most noticeable outlier.
The difference between his results against lefties and his overall results are greater than anyone except Nolan Arenado. That's just fine for Arenado (who is represented by the farthest point to the right). He crushed pitchers from both sides, but he just happened to really crush lefties.
Since San Diego signed Eric Hosmer to an eight-year deal earlier this spring, Renfroe has been the subject of trade speculation. For now, the Padres are determined to let Renfroe evolve. His upside is monstrous if he can somehow figure out right-handers.
"There's just a real confidence in him when he's facing left-handed pitching," Padres skipper Andy Green said. "I think that same confidence has been in him in the past against right-handed pitching. Last year didn't go well [against righties]. He's trying to make some physical adjustments to give him a better chance."
But sooner or later the Padres must answer the foremost question regarding their 26-year-old slugger: Is Renfroe destined to become an all-time great platoon hitter? Or can he be an effective everyday player?
If they settle on the former, Renfroe's value takes a hit. Right-handed pitchers are far more prevalent in baseball, and the most useful platoon players generally serve as multipurpose roster options. Renfroe isn't versatile, he's generally not a pinch-running option, and -- despite his other-worldly arm strength -- his defense has been sub-par.
Right now, Renfroe is competing for playing time with Jose Pirela, a fellow right-handed hitter who posted better numbers across the board in 2017. But there's platoon potential available for Renfroe, given Pirela's ability to play second base. (The Padres have two left-handed hitting second basemen -- Cory Spangenberg and Carlos Asuaje -- competing for that job.) They could also platoon Renfroe in the outfield with lefty-hitting Franchy Cordero.
It'd be a stark contrast to last season, when Renfroe started practically every day, regardless of opposing pitcher.
"There wasn't much of a time last year where we soft-served [Renfroe]," Green said. "He went up there against everybody. We didn't take him out of the lineup, we didn't platoon. We didn't try to make it easier on him.
"We definitely have the opportunity this year to do that, if we choose to. ... We have the opportunity to position him for success. But we've definitely not given up on his ability to hit right-handed pitching. We believe that he's going to get there."
If he doesn't, his at-bats will begin to dry up. If he does, Renfroe could become the middle-of-the lineup force the Padres always envisioned.