Now, entering Season 2, the Cubs are hoping Jackson at least lives up to his career norms, if not completely up to every dollar of his four-year, $52 million contract.
The 30-year-old right-hander went 8-18 with a 4.98 ERA and led the majors in losses while carrying a modest load of 175 1-3 innings, clearly not what the Cubs had in mind when they signed him.
He arrived in Chicago with a 4.40 career ERA, and he was coming off a 10-win season with Washington in which he had a 4.03 ERA. The Cubs were hoping for something close to that if not what he did in 2009.
That year, he went 13-9 for the Detroit Tigers while putting up a 3.62 ERA over 214 innings, and he threw a no-hitter the following season for the Arizona Diamondbacks. That happened against Tampa Bay on June 25, 2010, the second no-hitter in club history along with Randy Johnson's perfect game in 2004.
With the Cubs, Jackson said the pressure of the big contract didn't get to him.
''It's just a crazy year,'' he said. ''I don't think I was about to pull my hair out or stressing or pressing over games. It was just a crazy year where things didn't go the way I'd like. It just so happened to be the first year of a contract.
''I'm sure people expected more. But I expect more.''
He doesn't blame the results on Wrigley Field.
''The park plays bigger than you expect more times than not,'' Jackson said.
''You can catch an unfortunate day when the wind is blowing out. But for the most part, it plays big.''
''I think I just had an inconsistent delivery,'' he said.
Jackson is the epitome of the well-traveled athlete. For starters, he was born in Germany; his father served in the military.
Same goes for baseball. He debuted in 2003 with the Los Angeles Dodgers at age 19, and the Cubs are his eighth team.
Jackson believes he is secure enough in his career that he can use spring training to tweak his repertoire - he relies most heavily on fastballs and sliders - rather than worry about making the team or the starting rotation.
''Every year you want to improve on every aspect of the game,'' Jackson said. ''But for me, more important is consistent mechanics.''
So, as he starts spring training in 2014, ''I'm working on consistency. Staying consistent with all the pitches. Stay in the same arm slot, stay at the same speed, so everything looks the same.''
Jackson threw off a mound for the first time Saturday.
Pitching coach Chris Bosio, who was among the most interested spectators, said, ''Edwin pitched extremely well in some games, in others not so good.
''It was a tough year overall for the team. We have to look ourselves in the mirrors and ask everybody to get a little better. That's the message we're sending to everybody, including (fellow starters) Travis Wood and Jeff Samardzija.''
Also watching Jackson throw was new manager Rick Renteria, who judged his session ''pretty good.''
''He started a little up in the zone, then all of a sudden, he finished down, working multiple quadrants of the plate. Those are the simple things that he's going to have to do to get himself back to executing pitches. ... More than anything (he needs to) keep looking forward and focus on his job on a daily basis, pitch by pitch.''
''In his work, it's got to show. Today it did. He finished really strong.''
Renteria spoke with Jackson in the offseason and believes, ''Edwin has a really good outlook for this season. He's talked about putting last year behind him.''
For the Cubs' sake, he's got to succeed on more than a verbal level. He's got to return to his old form.