With the exception of David Wright and Jose Reyes, the Mets have had an uninspiring recent history of developing position players for the big club. Most notable has been their apparent inability (or unwillingness) to evaluate and earmark position players in the minor leagues with good plate discipline.

But help may be on the way. The Mets have a player in their system who seems to have a special ability to get on base, one whom they would do well to hold on to: Class A third baseman Grant Psomas.

Psomas, the Mets’ 15th rounder in 2004 out of West Virginia, struggled last year with Brooklyn in the batting-average department (.233) and hit just three homers, but, tellingly, he did have a solid isolated discipline of .077.

For those not familiar with it, isolated discipline is the difference between a player’s on-base percentage and his batting average. For instance, if a player is getting on base at a .350 clip but hitting .330, his isolated discipline is .020. This is a helpful stat because it measures plate discipline alone – if a player is hitting .330 but getting on base at .350, it means he isn’t walking very often, and therefore isn’t especially disciplined. If all those hits weren’t falling in, he wouldn’t be a very productive player. The major league average for ID has tended to fall between .060 and .070. It is especially helpful for gauging the ability of minor league hitters, whose batting averages can fluctuate as they move from park to park and league to league.

This year, the 22-year-old Psomas has broken out with the Hagerstown Suns, batting .299 with a .404 OBA and 17 homers in 311 at-bats. His ID has improved this year to .105, a 28-point spike. Psomas has 56 walks and 69 strikeouts this year; last year, in 223 at bats, he had 25 walks and 48 strikeouts.

This kind of improvement begs the question: How does a player who seemingly struggled with the bat last season make this kind of improvement? Well, that’s where stats like ID come in handy. The best indication of whether a player is overmatched at the plate tends to lay in his walk-to-strikeout ratio. While Psomas’s batting average and K/BB were only mediocre in his first season as a professional, his ID from 2004 was actually right in line with his stellar numbers from college; in his final two years at West Virginia, his IDs were .070 and .077. That .233 average in Brooklyn, it would seem, can be best attributed to that most common affliction of the newly drafted player: learning to hit with a wooden bat.

While not all experts give credence to this theory, the nice thing about ID is that it doesn’t favor metal or wood. Given Psomas’s continued improvement in his ability to reach base, his batting average struggle last year in Brooklyn could probably be attributed to a general lack of luck.

“Usually [the increase in OBA] means they learned the strike zone,” said one AL scout, on condition of anonymity. “If you’re a smart enough hitter, you’ll learn that as you move up the ladder, the guys in Low A, High A, they’ll throw you a breaking ball that runs off the plate, and if you swing at it, they’ll keep throwing it. But if you learn to identify pitches, you’ll get a chance to hit. If your strike zone is too big, you’ll have no chance.”

It’s helpful, then, to note the progress of a teammate of Psomas’s who also made the jump this season from Brooklyn to Hagerstown. Last year, in 155 at bats for the Cyclones, infielder Ryan Coultas hit .252 with an ID of .064 – not as good as Psomas’s, but close. This year, his average has gone up to .295, but his ID has actually gone down by 19 points to .045. For Coultas, it seems, the move to a more difficult league hurt his discipline – that is, he has struggled to get on base against more controlled pithchers. Meanwhile, Psomas steadily improved.

“As long as he hits, he has a chance to play,” said the scout. “He was one of the better hitters on the club. He might not be able to play third, but he throws well enough to move to the outfield. He’s more of a line-drive gap hitter, but it looks like there’s some power there.”

With Wright quickly establishing himself as the Mets’ third baseman of the future, it remains to be seen if the organization will take the time to move Psomas to the outfield. But if he maintains the kind of plate discipline he’s consistently shown and continues to improve, the Mets could eventually learn as much from Psomas as he does from them.