Baseball is back in Chicago.

Not literally, yet, as pitchers and catchers just reported to their spring training camps in Arizona last week, but figuratively, as expectations are elevated on both sides of town following a successful offseason.

The Cubs front office seemingly expedited their rebuilding plan this offseason, which has fans as excited for Cubs baseball as they have been since the arrival of team president Theo Epstein and general manager Jed Hoyer in 2011.

Epstein and Hoyer quickly reloaded their farm system upon their arrival, but expectations were limited for the major league team. After last season when big name prospects like Javier Baez and Jorge Soler made their way to the big league team, the rebuilding plan quickly progressed from laying the foundation to putting supplies together, ready to construct a contender.

The Cubs brass put together one of the most impressive offseasons in the league headlined by manager Joe Maddon and ace pitcher Jon Lester.

Coming off one of the best seasons of his career, the 31-year-old Lester will be the Cubs’ anchor in a generally underrated starting rotation. Lester’s FIP, or Fielder Independent Pitching  (a measurement of a pitcher’s performance that strips out the role of defense, luck and sequencing, making it a more stable indicator of how a pitcher actually performed over a given period of time), was an impressive 2.80 last season. For context, anything below 2.90 is considered excellent.

Lester was just one of the big free agents signed by the Cubs. They also acquired two-time All-Star catcher Miguel Montero, centerfielder Dexter Fowler, infielder Tommy La Stella and pitchers Jason Hammels and Jason Motte.

Those free agents will join cornerstones Anthony Rizzo and Starlin Castro in hopes of a playoff berth for the Cubs, the first since 2008.

Rizzo finished tenth in MVP voting last season with 32 home runs. He has improved in each of his three seasons with the Cubs. If that trajectory continues, Rizzo will quickly become one of the most feared hitters in baseball. Castro’s bat has been pretty consistent in his young career, but his focus and fielding both showed improvement last season. He should be set to enjoy a fourth All-Star season in 2015.

There is a possibility that we will see a few more of the Cubs’ highly touted prospects this season too, namely Kris Bryant who has dominated both Triple-A and Double-A and is widely thought of as the top prospect in baseball. If the young Cubs can continue to grow as Rizzo and Castro have, this team really is a contender.

They are not the only team in town with championship aspirations, however.

The White Sox also enjoyed one of the best offseasons in baseball.

The biggest move for the Sox was the addition of former Cub starting pitcher Jeff Samardzija. The 30-year-old righty should be a rock solid No. 2 pitcher behind perennial Cy Young candidate Chris Sale. Jose Quintana, John Danks and Hector Noesi fill out the Sox rotation. Quintana was a quality No. 2, so he should be one of the best No. 3 pitchers in baseball; Danks and Noesi both showed flashes last season of being great back-end of the rotation pitchers.

They also added reliable bullpen arms with David Robertson and Zach Duke, as well as veteran bats in Adam LaRoche and Melky Cabrera to bat both in front of and behind superstar Jose Abreu.

If the White Sox position players stay healthy, they boast one of the deepest lineups in the American League Central division. Outfielders Adam Eaton and Avisail Garcia both missed significant time last season due to injury, and both are key parts of the Sox lineup. Eaton was not only the spark plug of a revamped offense last season, but he also finished the year as a Gold Glove finalist for his determined outfield play. His fearlessness in the outfield resembles that of former Sox fan-favorite Aaron Rowand.

While the outfield is set with Cabrera, Eaton and Garcia, the infield still has some positional battles that need to play out. Abreu and seven-year veteran Alexei Ramirez solidify first base and shortstop, but questions still remain at second and third base. Former starting second baseman Gordon Beckham was reacquired, but is expected to play a more utility role while youngsters Carlos Sachez and Micah Johnson battle it out at second. Sanchez probably has the upper hand as he played almost 30 games with the big league team last season, but Johnson’s upside may be enough to earn him the starting position. Last season’s starting third baseman Connor Gillaspie returns, but still leaves much to be desired. Playing a traditionally powerful position, Gillaspie had just seven home runs last season. He has put on 15 pounds of muscle in the offseason, but as a line drive hitter, it’s hard to see him ever putting up big power numbers. If the Sox can get quality play out of those two positions in question, they should be contending for the A.L. Central come August.