MESA, Ariz. -- When the White Sox traded a pair of pitching prospects to Arizona for Edwin Jackson in July of 2010, on paper the team received a starter with a 5.16 ERA and little success in his previous 7 1/2 major league seasons. That's not the kind of pitcher who a team trades top talent for, nor is that the kind of pitcher who eventually receives a four-year, $52 million contract as a free agent.
Something clicked with the White Sox, though. At the urging of pitching coach Don Cooper, Jackson stood taller during his delivery. As a result, he began to throw more first-pitch strikes. And with that came the level of success that ultimately landed Jackson his big deal with the Cubs.
"(Cooper) just told me stay tall and watch the glove. That was pretty much it," Jackson said Sunday at HoHoKam Stadium. "Simplified it and everything else was keep doing what I had been doing."
Dioner Navarro caught Jackson while the pair were with Tampa Bay. Back then, Jackson was in his early 20's, trying to marry a powerful arsenal of pitches with statistical success. But the ace potential so many thought Jackson had never materialized.
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"The biggest thing to us was to throw strikes," Navarro, who signed with the Cubs in the offseason, said. "That's a big difference, he throws a lot more strikes now than he did back then. He's a lot more efficient nowadays."
With Tampa Bay, Jackson never had a first-pitch strike rate of over 54.7 percent -- well below the MLB average of 58-59 percent. His lowest ERA was 4.42, but his FIP -- a statistic which measures a pitcher's ability to do the things he can control -- hovered just below 5 as a starter.
Jackson had success with Detroit in 2009 with a 3.62 ERA, but it didn't carry over to 2010 with Arizona. Despite throwing a no-hitter, Jackson's ERA wasn't good when he was dealt to the White Sox.
As a member of the White Sox, Jackson made 30 starts and posted a 3.66 ERA with 174 strikeouts and 54 walks. Current Cubs utilityman Brent Lillibridge played with Jackson on the South Side, and offered an observation that still holds true in 2013.
"When he's on, he's fun to be around," Lillibridge said, "because you're not going to get a lot of action because he's going to be striking out a lot of guys and missing a lot of barrels."
Nearly three years later, a lot has changed for Jackson. He's finally enjoying some stability after bouncing from Chicago to St. Louis to Washington. He's no longer a young pitcher who couldn't harness his potential -- he'll turn 30 in September. His mechanics have changed a bit, too, although he still keeps Cooper's recommendation in the back of his head.
"It was definitely a helpful piece of advice," Jackson said. "The only difference now is I have different mechanics. You still have to implement standing tall into the new mechanics that you have."
By getting ahead in the count more often, Jackson was able to more effectively set up his slider late in counts. From 2007 through his trade to the White Sox in 2010, Jackson threw his fastball 65.6 percent of the time, while offering his slider on 23.1 percent of his pitches (per Texas Leaguers' pitch f/x database). He threw his changeup 8 percent of the time, a pitch Navarro considers a key for the right-hander.
After coming to the White Sox, Jackson threw his fastball less (52.8 percent) and his slider (34.9 percent) and changeup (9.9 percent) more. Jackson generated more swings and misses on his slider and changeup, too, and threw both pitches for strikes at a higher clip. Over the last two and a half season, Jackson's ERA has sat under 4.
Not all of Jackson's success should be traced back to the White Sox -- a lot of it, both he and Navarro admitted, came from the growth that's the product of more experience.
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"Every year, it's that process," Jackson explained. "You continue to be more consistent with every pitch, and feel like you can throw whatever pitch in any count wherever you want to and whenever you want to. That's pretty much the goals of everyone in the game, throw what you want when you want where you want."
For Jackson, the formula added up to $52 million and, potentially, four years of stability. When Jackson takes the mound for the first time in a Cubs uniform, it'll be the seventh team he'll have played for since 2008.
The constant change didn't faze Jackson, who was born in West Germany as a "military brat."
"The only life I know is on the go, so it’s not bad," Jackson said earlier this spring. "I’ve been living out of a suitcase for a long time.”
Jackson can finally unpack that suitcase, and settle down for a future he sees as bright with the Cubs. Navarro, too, expects to see a different pitcher than the one he caught with Tampa Bay.
"After bouncing around few different teams, now he finds himself in a position where he doesn't have to think about where he's going to be next year," Navarro added. "I think that's going to help him a lot, and I think he's going to do a really good job for the Cubs."