There was a time, during RAB’s halcyon days, when Jose Tabata invited encouraging comparisons. The name Manny Ramirez appeared frequently, which left Yankees fans salivating. Even better, when Baseball America rated him the Yankees’ No. 2 and the No. 27 overall prospect in 2007, they said that he “has the talent to reach New York by the end of 2008.”

By the end of 2008 not only was Tabata not in the majors, but he wasn’t even in the Yankees system. On July 25th, 2008, when they sat three games back of first and were starting a series against Boston, they pulled off a major trade in which Tabata was the centerpiece. They sent him, along with Jeff Karstens, Daniel McCutchen, and Ross Ohlendorf to the Pirates in exchange for Damaso Marte and Xavier Nady. In Marte they got a lefty reliever — one whom they once traded for Enrique Wilson — and a right-handed outfielder in the midst of a career year. The Yankees certainly needed the help that Marte and Nady could provide, but losing Tabata still stung a little.

While Tabata possessed plenty of upside, his attitude and antics certainly soured the Yankees. After all, the same Baseball America scouting report that glowed about his “innate ability to get the fat part of the bat to the ball quickly, consistently, and with power,” also said that the “tends to cost and turn his talent on and off.” He stormed out of one game and considered quitting. That doesn’t even touch on his decades-older wife, who was accused of kidnapping a baby. In 2008 all that appeared to catch up to him, and he sported a mere .248/.320/.310 line in AA prior to the trade. The Yankees’ patience, apparently, wore thin.

Even with the reinforcements the Yankees couldn’t overcome their depleting pitching staff. At that point Chien-Ming Wang was already done for the year, and Joba Chamberlain had just a few starts remaining before he, too, would go on the DL. Marte pitched well at first, but after a long outing in Texas (I believe on the same day Joba got hurt) he was apparently gassed. Nady stumbled in his new digs. It amounted to a 32-28 record post-trade, which was actually worse than their pre-trade record. The Yankees missed the playoffs for the first time since 1993. The only bright side was that they had Nady and Marte for at least one more season each.

With Nady, they ended up with essentially nothing. The Yankees named him the starting right fielder in 2009, despite Nick Swisher’s presence on the roster, but he suffered an elbow injury a few games into the season and didn’t play another one until 2010 with the Cubs. His time with the Yankees amounted to 0.6 WAR. Instead of exercising Marte’s $6 million option for 2009, the Yankees signed him to a three-year, $12 million contract. He’s spent most of it on the DL, though he did come through in the 2009 World Series. The only way the Yankees won this deal was with the old saying, flags fly forever. (Though I suppose that assumes that the Yankees would not have won the series without Marte, which is debatable, to say the least.)

Karstens, McCutchen, and Ohlendorf were mere afterthoughts in the trade. Ohlendorf broke camp with the 2008 team as a reliever, though his role was never clear. Whether that made him seem worse I’m not sure, but it’s impossible to define his stint with the big league club as successful. He might have helped in the future, but the Yankees had plenty of other mid-range pitching prospects. The same goes for Karstens and McCutchen. Both had their bright spots, but both were fungible assets. There was little to argue about when trading them, and even using hindsight, with Karstens experiencing some success this year, it’s hard to find fault with trading these guys. It was actually a Yankees fan’s dream: trading middling non-prospects for actual major leaguers.

Tabata, on the other hand, represented someone the Yankees could actually use. The system has lacked power corner OF bats since RAB started in 2007, and Tabata was the one guy who could have grown into that type of player. But given all his issues both on and off the field, they apparently thought he wasn’t the best fit. And despite all the hype, he has never hit for power — not in any stop in the minors in which he had more than 100 AB, and not in the majors.

The lack of power brings up an important question when evaluating the Tabata trade: where would he have played? Even if the Yankees were a bit aggressive with him, as the Pirates were last year, where would he have fit? Last year Brett Gardner was working on a breakout year, and the Yankees had Nick Swisher manning right field. From 2010 to 2011 Nick Swisher has produced a .367 wOBA and Gardner has produced .351 (9th and 20th among qualified MLB OFers). Tabata, meanwhile, has produced a .332 wOBA, and that’s pretty evenly divided between his two seasons. (It would rank 40th if he were qualified.)

It was impossible to know at the time, of course, that the Yankees would acquire Swisher and develop Gardner into a borderline elite player, so all of that represents hindsight evaluation in one way. But in another it represents a legitimate viewpoint, since Tabata wouldn’t have been ready for the majors until the Yankees started to see what they had in those two players. Even if he miraculously broke out in 2009 the Yanks wouldn’t have had room for him.

This weekend Tabata was rewarded for his 3.5 career WAR, and his potential for more, with a five-year extension worth a guaranteed $14.25 million that could end up a eight-year, $36.75 million deal. With the Yankees he never would have gotten that opportunity. With Gardner and Swisher taking over the outfield corners in the past two years, he would have remained blocked. That could have worked out if he turned things around in the Yanks system; they could have traded him this past winter, perhaps for a starting pitcher. But if he continued to falter they would have gotten even less. The Yanks apparently saw that risk ahead of time and dealt him while at least one team still valued him.

The hardest part of reconciling these past trades is figuring out how the Yankees would have fared had they not made the trade. It’s especially tough in this situation, when they got so little value for the return, but also wouldn’t have had room for the centerpiece. While it was a clear loss for the Yankees — they gave up something of value to another team and got little value back — the real-world effect isn’t that great. It would have taken a big turnaround from the disappointing Tabata in order for the Yankees to realize any value from him in the future.