Who is Tigers rookie Jefry Marte?

Detroit Tigers rookie Jefry Marte collected his first major league hits yesterday, going 2-for-4 with a homer and two RBI in Detroit's game against the Seattle Mariners.

Earlier today we discussed Atlanta Braves catcher Christian Bethancourt and the fact that his skills and performance have never matched the talent perceived by scouts. Marte is another example of that principle, albeit in a different way and a case that looks like it will have a good outcome.

The New York Mets signed Marte for $550,000 in 2007 out of the Dominican Republic. At the time he was considered one of the top power hitters available on the international market. He went directly to the Gulf Coast League in 2008 (skipping the Dominican Summer League) and hit extremely well, .325/.398/.532 at age 17, with decent strike zone judgment to go with strong overall production.

The Mets at the time loved moving Latin American prospects aggressively and they moved him directly to Low-A Savannah for 2009 at the age of 18. It didn't work. He hit poorly (.233/.279/.338) and improved only marginally in 2010. He wasn't much better at High-A St. Lucie in 2011 (.248/.313/.346). But the Mets kept moving him up, onward to Double-A Binghamton in 2012 with a .251/.322/.366 mark.

At that point the Sandy Alderson regime pulled the plug and traded him to the Oakland Athletics. Little changed: he hit .278/.349/.388 in Double-A in '13 and .259/.333/.375 in 2014. Now, that's not terrible. His wRC+ marks were actually a little above average both years (105 and 107 respectively) and the Texas League is no longer the hitter paradise it once was. But it was a far cry from what was originally expected.

The Tigers signed him as a minor league free agent for 2015 and suddenly everything has changed. He hit .271/.337/.497 with 13 homers and a 139 wRC+ for Triple-A Toledo this spring, leading to his recent promotion to the majors. Keep in mind that's the International League, a generally neutral environment, and Toledo is a considered a pitcher's park. The surge was predicated on a hot June: he hit .319/.385/.622 in the 30 games before his promotion.

Just a hot streak that he's ridden into the majors? Maybe. But keep the following in mind:

***Even when he wasn't hitting particularly well in the lower and middle minors, Marte was not a wild hacker: he fanned 117 times in Low-A at age 18, but since then his strikeout rate has trended downward, quite strongly. He's never fanned more than 86 times in a full season since his initial Low-A exposure and his overall strikeout rates have continued to decline, from 22% in '09 to 17% in '13 down to 15% the last two years.

***His walk rates started off very low (less than 5% at age 18) but gradually increased, up to just under 10% last year. That's not exceptional but the steady increase in walks combined with the concurrent decline in whiffs speaks to slow but real progress learning the zone.

***Physical strength is not the issue; his raw power has always been rated quite well but his swing was geared for line drives. Fangraphs noted earlier this week that Marte's ground ball/fly ball ratios have made a sudden switch this year. He has been a ground ball/line drive hitter for his entire career but in 2015 he's suddenly almost doubled his fly ball ratio. And given that he's strong, more homers are the natural result of more fly balls. We'll have to see if that is a permanent change, but it fits the theory that he's made a change in his swing since joining the Tigers.

***Despite a strong throwing arm and adequate range, Marte's results as a defender were poor for much of his career. He led all minor league players with 49 errors in 2009 but since then the error totals have gone down considerably. They are still too high and he will never be a gold glove, but his footwork is better than it used to be and this is another factor pointing to a player who has worked hard to improve.

***Although he has been around forever, Marte is still just 24 years old, young enough to show genuine skill growth.

Overall, although it doesn't look like Marte will live up to the full star-like potential he showed way back in rookie ball, he has made real improvements in his baseball skills and the change of scenery with Detroit seems to have done him some good. He can be a useful role player, and it would not surprise me to see him have some very good seasons when he reaches the age 26-27 window.