I am a big believer in Josh Donaldson. If his defense was a little better he would be the A's number 3 prospect on my list a head of Brett Wallace.  Find out why you should be too and you should vote for him as the #4 prospect in Zonis' community poll after the fold.

The first thing that I like about Donaldson is his plate discipline. He has a career 153/200 BB/K ratio and 85BB to 99Ks on the year (including playoffs).  He has a career .374 OBA which was .380 this year.  This year he has walked in 15% of his regular season plate appearances.  This is very very impressive especially for a catcher and could allow him to be a very very very good baseball player.  His ceiling is very high despite people thinking otherwise.  If Donaldson walks in 15% of his MLB PAs and gets 600 PAs Donaldson will walk 90 times on the year.  If he hits .275 in his 510 ABs that is 140 hits. Combined he would have a .384 OBA.  Donaldson has never had a below .132 ISO and has 15 hr potential so when you project slugging his ceiling around a .150 ISO leading to a .425 SLG.  A .275/.384/.425 slash line is approximately a .359 wOBA.  This year that would be good for 16 BRAA.  With a 12.5 run positional adjustment for catching and 20 runs for replacement Donaldson would be 48.5 runs above replacement without factoring in defense.  If his upside behind the plate is -5 FRAA then he has All-Star upside as a 4.3 WAR player.

 

If he hits .260 which is below his career aver in the bigs and maintains his even a decreased walk rate (12.5% or 75 walks over 600 PAs) he still gets 136 hits and has a .353 OBA.  With a .125 ISO (which is below any of the minor league seasons hes had to date) he slugs .385.  He still has a league average bat with a .328 wOBA.  when coupled with replacement runs, position, and assuming -12.5 FRAA defense behind the plate he still projects to be a league average player.

If he is forced to move back to his college position at third base he won't get the positional bump but he should be able to provide league average defense there since reports were that he was a good fielder in college.  

Pgcrosschecker.com

SCOUTING REPORT: Donaldson is a first-rate defender at third base, but his profile plays better behind the plate and he began a successful conversion to catching a year ago, successfully completing the transition this year.

Also from his MLB draft profile. Link:

Fielding: Donaldson is new to full-time catching, but has good hands and caught fairly well. Some think he’s athletic enough to handle a Biggio-like move to second.

Some see a switch to the infield — he’s played third in college — but he may make for a good backup catcher who plays the game the right way.

More PG

In games Donaldson isn’t behind the plate, he’s at third base, as he has the lateral quickness and incredibly strong arm to play either position. He has alternated between the two positions the last couple of years after starting his college career as a full-time third baseman, so he is still a little unrefined behind the plate, but has the tools to succeed there.

The positional adjustment for catchers is 12.5 runs where as it is only 2.5 runs at 3b.  If he moves to 3b I expect him to be a league average 3bman defensively (though there is potential for him to be better). If his upside is +5 FRAA at 3b his upside projection as a catcher is still valid at 3b.  Reports of his poor defense behind the plate, while coupled with some that say he has improved slightly, suggest that he could be a -10 FRAA as a catcher.  Therefore moving him to third loses him 10 positional runs but he gains +10 FRAA, as the his defense when compared to his peers is significantly better at the hot corner, using reasonable projections making the switch likely to have a negligible effect on his value.

Because Josh Donaldson has All-Star (4+WAR) upside at two positions and conservative projection puts Donaldson as a league average player at either of those two positions,  you should vote for Donaldson as the number 4 prospect in the A's system.