Not A Rookie: Joe Mather
Joe Mather was drafted by the Cardinals in the third round in 2001, out of high school in Phoenix. A shortstop in high school, he impressed scouts with his size, athleticism, and power potential, but was considered rather raw. The Cardinals moved him to third base, and he hit .248/.288/.358 for Johnson City in the Appalachian League. I didn't rate many short-season players back then, but would have given him a Grade C: toolsy, but unrefined. He posted a 7/60 BB/K ratio in 165 at-bats, demonstrating huge problems with contact.
Returned to Johnson City in 2002, Mather hit .232/.320/.424, boosting his power production and improving his plate discipline, substantially cutting his strikeout rate. I would have given him a Grade C again, but might have seen some sleeper potential given the improvement in his discipline.
Mather moved up to the New York-Penn League in 2003 and struggled, hitting .230/.314/.332 in 65 games, mostly at first base. I wasn't thinking of him as a prospect at all at this point, and a Grade C rating would be appropriate.
The first time I saw him play was in 2004. He hit .253/.333/.432 in 65 games for Peoria in the Midwest League, now playing mostly outfield. This was improved performance, and I remember being impressed with his size and strength on the field, though he still needed to sharpen his strike zone judgment and contact ability, fanning 70 times in 241 at-bats. I didn't put him in the 2005 book for space reasons, but had him rated as a Grade C.
Mather split 2005 between Quad Cities in the Midwest League (.220/.295/.440 in 54 games) and Palm Beach in the Florida State League (.275/.342/.475), hitting 17 homers. Strike zone judgment remained an issue, and to be honest I kind of forgot about him as I was writing the 2006 book, paying more attention to the Midwest League line than the FSL line. He'd still rate as a Grade C in retrospect.
Mather hit .269/.333/.457 in 124 games for Palm Beach in 2006. I had him as a Grade C in the first draft of the 2007 book, but cut him for space reasons, since he was now 24 years old, was still struggling with the strike zone, and didn't look to me like a great candidate for success at higher levels.
He made that look like a very bad call in 2007, when he hit .303/.387/.607 for Double-A Springfield in 64 games, then .241/.329/.443 in 70 games for Triple-A Memphis, combining for 31 homers. I got a good look at him in for the first time since 2004, and it was clear that he had made some real progress refining his command of the zone. I gave him a Grade C+ in the 2008 book, writing that he could be "a .240-.250 hitter but with plenty of power and the occasional stolen base."
Mather hit .303/.411/.630 last year in Triple-A, then .241/.306/.474 in 54 games for the Cardinals, just pushing past the rookie at-bat limit.. He was in the "play third base until Troy Glaus is healthy" hunt this spring, but right now it looks like David Freese has the inside track on that job.
What we have in Mather is a tools guy who gained just enough polish to let his talent come through in at least a moderate way. I don't think he'll ever hit for a high batting average, and I think his baseline is as a .250 hitter, with enough power to be useful. But remember, a "baseline .250 hitter" can hit .280 (or .220) in any given year based on luck. The PECOTA comps are instructive: Ozzie Timmons, Scott Hairston, Ryan Ludwick, Joe Charboneau, Craig Monroe, Wes Chamberlain, Jason Lane. Another possible comp would be Shane Spencer.