jon jay has had an odd profile as a major leaguer for a while.

he's parlayed a one-trick pony skillset into a starting role as a centerfielder. he doesn't hit for power, with a career ISO of .109. he's not a plate disciplinarian like matt carpenter or mike o'neill; he has a subpar walk rate (6.9%). he is not a plus-plus centerfielder like shane robinson.

the one thing he does well . . . er, did well . . . is/was hitting for average. he has hit .300, .297, and .305 over the last three seasons. that kept his OBP up and made him a pretty valuable guy. but that came with a caveat. across 2010, 2011, and 2012, he hit for an improbably high .340, .350, and .355 BABIP. many commentators hung some pretty big red flags on him for that.

after sustaining that BABIP for 1300+ PAs, a lot of jon jay fans were willing to be that there was a lot more substance than illusion to his batting average. maybe he wasn't a .300 hitter by his true talent, but he might be a .285-.290 kind of guy. even with his other shortcomings, anticipating that production made him palatable, though not a superstar.

then came 2013. 324 PAs into the season, he's hitting a paltry .245, which is dragging down his one area of value. combine that with a huge and likely unreliable defensive rating as a centerfielder, and he gets rated as below replacement value so far.

so, let's take the easy thing first. by now, most readers are aware that defensive ratings are pretty useless in a half-season, or even one-season samples. it is highly unlikely that jon jay went from an average centerfielder to one of the worst in MLB. a -16 UZR/150 puts him way down with first-time-ever CF shin soo-choo. jay is probably still an average-ish CF (with a terrible arm).

the tougher thing is his batting average. and i am stumped, honestly. the guy just lost 60 points of BABIP, and 60 points of batting average overnight, without substantially changing his peripherals.

he's still walking more or less okay; in fact a little better this year (8.4%) than for his career (6.9%).

he's not striking out more (16.3% K rate) relative to his career (15.4%).

he's generally making harder contact (23.2% line drive rate) relative to his career (21.8%).

he's not popping up appreciably more (25.9% FB rate) relative to his career (24.2%).

his power-hitting profile has not changed much (.086 ISO v. .109 ISO for his career).

he is hitting fewer grounders than previously, which could be part of his BABIP dip. his groundball rate is 50.9% versus career numbers of 54.1%. since the likelihood of a ball in play is higher for a groundball than a flyball, a small dip in his groundball rate and a modest increase in his flyball rate would hurt his BABIP, but not 60 points worth. and his increased line drive numbers should make up for most of the lost grounders.

his contact and plate discipline numbers have not changed much. his swing rates and contact rates are virtually the same as his career numbers.

nobody is pitching differently to him; he's seeing essentially the same distribution of pitches.

while the temptation is to say that anyone who hits so badly over 300 PAs has really lost something, there are plenty of examples of people who struggle for a half-season and go back to normal. ben zobrist hit .242 in the first half of 2012, then came back to hit .292.

on the other hand, there's no assurance that jay will come back and be his 2010-2012 self. he was not a great bet to start out; i'd have a lot more faith in a more well-rounded player, who would not become essentially useless once that one skill starts to slip.there could be something seriously wrong with jay.

to my eye, though, it would be very odd to see some collapse at the plate that results in no change in your strike out rate, little change in your walk rate, and little change in your batted ball profile. if jay were striking out a lot more, or popping out at a surprising rate, i'd buy the collapse theory. but the evidence for it is missing. until i see otherwise, i'd guess he's just going through an ordinary half-season struggle rather than a full-on collapse. i'm ready to be proved wrong.

the other thing which is difficult to assess is whether our original estimation of jay was at least partially wrong. 300 PAs is not a huge amount of playing time, but it's not nothing. it may very well be that we were too optimistic at the outset. i highly doubt jon jay was originally a true talent .250 hitter or has become one, but it's very possible that he was a true talent .270-.280 hitter who played over his head for two-and-a-half years. if so, jay's long-term role with the cardinals shifts from starting center fielder to role player (no, ladies and gents, he is not trade bait, however much you might wish it; selling low on jon jay will net us very little).

the good news, or maybe better stated, the simplifying news is that there's no reason not to let this run its course and see if jay recovers. there simply isn't a very exciting CF option available in july or august. shane robinson is probably not any better in a regular starting role, though it wouldn't be a terrible idea to let him take the field more against lefty starters. oscar taveras is currently injured and not ready to take up a starting role for the cardinals in the next month or so.

the rest of the upper minors is pretty bereft of MLB-ready talent. adron chambers remains replacementastic. tommy pham has been serving mostly at AA and the DL, although he's fared well on the former. mike o'neill is impressive in his completely bizarre way, but is probably not a starting centerfielder and is still playing at AA.

but, unless taveras's injury is worse than currently advertised, it doesn't make much sense to look for a trade on the open market either. taveras is not ready to step up this month, but he's not very far away. it doesn't make much sense to make a major trade for someone who would quickly become part of a taveras/holliday/beltran/craig/adams logjam in the outfield and first base.

there aren't a lot of readily available CF at the deadline, although the cubs might be ready to trade david dejesus. colby rasmus has been worth 2.2 WAR so far this year, but that ship has probably sailed.

* * *

this last month has certainly been frustrating. we lost a lot of tantalizingly winnable games, we saw blowups from otherwise reliable starters, and we failed to capitalize on opportunities against truly terrible teams.

in june 2013, we went 14-14, with a .500 record. nobody with the talent the cardinals have should be happy about that. but at the same time, we should probably keep the sackcloth and ashes out of sight.

in 2012, by this date, we had finished two consecutive months with losing records: in may, we had a 13-16 (.448) record; in june, we had a 13-14 (.488) record. that year, we made it all the way to the NLCS.

in 2011, we had a 11-15 record in june, for a .423 record. as you may recall, that season turned out okay, too.

we're two games out, playing over .600, with half a season to go and the second-best record in the NL. cheer up.