5 intriguing Red Sox projections

Baseball projection systems aren't a toy, but they also aren't gospel or a guarantee that certain things will happen for sure. They're a helpful guess, albeit a sophisticated one, at what could go on with a team or a player or the league as a whole. This mostly means that projections tend to need a little more explanation than whatever stat line they spit out, and that's our goal here today: we'll look at five Red Sox projections from Baseball Prospectus' PECOTA system that stood out, whether that was for good or bad reasons.

Mookie Betts is Boston's best player

This looks... optimistic. Betts could absolutely be the best player on the Red Sox in 2015, and PECOTA projects as much by assigning him a team-leading wins above replacement total. He was a fantastic defender at second base in the minors and has shown an aptitude for the outfield, including center, in his short time playing out there. He was hugely impressive at the plate at every level in 2014, including in the majors, where he batted .291/.368/.444 in 213 plate appearances while showing an approach at the plate that belied his age (21) and inexperience. Teams have had a winter to analyze him now, however, and while it's a possibility he picks up where he left off, projecting him there seems a tad silly. Or have we already forgotten about Xander Bogaerts?

With that being said, it still does make some sense. PECOTA doesn't project any Red Sox hitter for a huge season, but instead thinks every single starter is going to be productive, meaning they're a solid lineup with no holes -- one PECOTA projects to score the most runs in the league. Christian Vazquez is the closest thing, as he's projected to a well below-average line, but he's also a tremendous defensive catcher who isn't projected to be an outright drag on the lineup: between his and Ryan Hanigan's glove, Boston will do alright behind the plate, too. Betts might be forecasted as the best of the bunch, but PECOTA has him down for .280/.356/.417 -- it's not exactly an otherwordly line. It's very Dustin Pedroia-ish, though, and Pedey has taken his turns as Boston's best player thanks to his combination of bat and glove, so hey, it could happen.

Xander Bogaerts isn't breaking out just yet

This is a simple one to explain. Bogaerts dominated the minors, yes, but a projection system is going to put more stock into his major-league numbers, especially since the shortstop has an entire season's worth to look towards now. PECOTA sees Bogaerts batting .255/.317/.398, which sounds pretty meh, but is actually pretty good when you consider how weak shortstop is: that's a .268 True Average*, whereas shortstops as a whole were at .256 last season, and in 2015 will no longer have Hanley Ramirez's bat in that mix with his move to left field. It's also worth pointing out that this is Bogaerts' mid-range projection, as those are the only ones available from PECOTA at the moment: when the percentile forecasts come out, we'll get to see the best- and worst-case scenario forecasts that informed this middle ground one. You can bet that the high-end involves a player projected to be one of the best bats at his position.

*True Average (TAv) is the BP equivalent of wOBA, except it's on a batting average scale. League-average is always .260, unlike wOBA, which uses a moving average. This has been today's lesson in baseball stats.

Even if this is all Bogaerts' accomplishes in 2015, it's worth remembering that it's a step up from last season, in which he hit .240/.297/.362, and that he's also considered the second-worst hitting starter on the team. If your second-worst hitter is an above-average shortstop, you're doing something right. And he's still just 22: there's time to break out yet, if he doesn't get to it this summer.

Clay Buchholz will be Boston's ace

Well, nominally, anyway. Buchholz is the only Red Sox starting pitcher that PECOTA doesn't actively hate, and even then that's questionable, as it only projects him for 144 innings of 3.83 ERA ball. This is no reason to panic, by the way. PECOTA isn't telling us anything we weren't already aware of here. We knew Rick Porcello isn't a lock to replicate his career-best 2014. Justin Masterson might not return to form. Joe Kelly hasn't proven he's a useful American League starter yet. Wade Miley is... okay, their Wade Miley projection for a replacement-level season is flat out bad, given he'll be in front of a better defense and has been great in the not-so-distant past. Do better, PECOTA.

Like with Bogaerts above, this is an area where the percentile forecasts will paint a better picture. Of course the mid-range projection for Masterson is going to be uninspiring -- the worst-case scenario for him is career-killing, whereas the top-end is very good starting pitcher. That doesn't balance! It's way underselling Porcello, likely by not giving enough credit to Boston's infield defense, or by not laying enough of the historical blame for Porcello on the Tigers' terrible infield. It's probably being far too harsh on Kelly, and this is coming from someone who thinks Kelly is a fifth starter. It is dumb and bad about Wade Miley, but we've covered this and I don't want to accidentally overemphasize how dumb and bad his dumb and bad mid-range projection is.

Koji Uehara will be Boston's most valuable pitcher

You know why there is a vacancy for this already unless you skipped the previous two paragraphs, but PECOTA also expects the 40-year-old right-hander to keep on dominating and doling out celebratory high fives. Koji is projected for a 2.07 ERA and 1.8 wins above replacement in 58 games. He'll pitch more than that if he's healthy, so he'll be worth even more from a wins perspective, but the key here is that PECOTA isn't frightened by the prospect of a 40-year-old closer in the AL East. Neat, right?

Your AL East champion Red Sox

Well, sort of. PECOTA actually projects the Red Sox to be tied with the Rays for the AL East lead, with whichever loses the one-game melee taking the second wild card spot. They get there in completely different ways, too: the Rays allow the fewest runs in the American League behind a strong rotation and incredible defense while scoring the fourth-least, and the Sox lead the world in runs scored while their pitching staff gives up more runs than all but three teams in the game.

On the bright side, if the Rays beat the Red Sox in this hypothetical AL East title shot, at least Joe Maddon won't be there to smirk at us afterward.