Boston Red Sox
2015 record: 78-84 (fifth place, 15 games back)
Key additions: The Red Sox's big offseason began in early December when they signed left-hander David Price, one of the top two pitchers on the free-agent market and a 2012 Cy Young Award winner. They also made a pair of high-profile trades to strengthen the back of their bullpen, where longtime closer Koji Uehara showed his age a bit last season. They sent a package of prospects to the San Diego Padres for former All-Star closer Craig Kimbrel, then added hard-throwing reliever Carson Smith in a trade that sent starter Wade Miley to the Seattle Mariners. Also, new team president Dave Dombrowski rounded out Boston's bench by signing Chris Young to a two-year deal to back up the club's young, talented outfield.
Key losses: A pair of left-handers who started a combined 36 games for the Red Sox last season, Miley and Rich Hill, left the club this offseason. Hill, who worked his way back from arm problems to become one of the feel-good stories of 2015, signed a one-year deal with the Oakland Athletics.
X-Factors: Hanley Ramirez and Pablo Sandoval
A year ago, the additions of third baseman Pablo Sandoval and infielder-turned-outfielder Hanley Ramirez were thought to improve a great young lineup. But the two players battled injuries and defensive ineptitude, and the Red Sox were much better without them. This year, Ramirez is playing first base and Sandoval battled with Travis Shaw for the third base job in spring training. Can this team get production from them? And if not, will the clubhouse situation become untenable?
Outlook: Even with those questions, there's plenty of production in Boston's lineup with young stars Mookie Betts and Xander Bogaerts. The Red Sox might not have enough starting pitching, but the second half of 2015 featured big steps forward by Rick Porcello and Joe Kelly. Those two, plus Price, give Boston one of the better rotations in the division when they're on. If that clicks, and the lineup hits to its potential, the Red Sox will be battling for the division title this year.
New York Yankees
2015 record: 87-75 (second place, six games back; lost in wild-card game)
Key additions: They won't be able to call on him for the first month of the season, but the Yankees' acquisition of reliever Aroldis Chapman from the Cincinnati Reds added to an already lethal bullpen that includes former Oriole Andrew Miller and Dellin Betances. Chapman is suspended 30 games for a domestic-violence incident in October. New York also traded pitcher Adam Warren to the Chicago Cubs for infielder Starlin Castro, who hit 11 home runs with a .671 OPS last year. He'll play second base. And the Yankees traded for outfielder Aaron Hicks, who had a good second half with the Minnesota Twins last season and will be a strong fourth outfielder. Amazingly, they didn't spend a dime in free agency to improve the major league roster. These aren't your older brother's Yankees.
Key losses: That relative lack of spending was because there wasn't a lot for the Yankees to do — they lost only backup infielder Stephen Drew, fourth outfielder Chris Young and Warren. Warren would have been a useful piece of starting depth in a rotation with plenty of uncertainty, but he was deemed to be surplus.
X-Factor: The starting rotation
The Yankees have a neat mix of overpaid veterans and interesting young players in their lineup, but will go only as far as the rotation takes them. Left-hander CC Sabathia was better toward the end of 2015 but had to check himself into rehabilitation for alcohol in October and had a rough spring. Right-hander Masahiro Tanaka dealt with arm injuries for a second straight year and had a 3.51 ERA in 24 starts. Michael Pineda and Nathan Eovaldi both have too much talent to post ERAs above 4.00 as they did last year, and the lone young arm is Luis Severino. The Yankees need everyone to click to have a chance.
Outlook: The Yankees were called the most underrated team in baseball by FanGraphs this offseason, and while that's difficult to say about a 2015 playoff team that's filled with stars, they're certainly in contention for a return to the playoffs.
Tampa Bay Rays
2015 record: 80-82 (fourth place,13 games back)
Key additions: Many think the Rays got a bargain this offseason — a player with whom Orioles fans will be familiar. First baseman-outfielder Steve Pearce received a one-year, $4.75 million deal this offseason after becoming a free agent and adds some power to a light-hitting Tampa Bay lineup. Other newcomers include shortstop Brad Miller and outfielder Corey Dickerson. Miller, acquired along with first baseman Logan Morrison and reliever Danny Farquhar from the Seattle Mariners, hit a career-high 11 home runs with a .731 OPS last season. Dickerson came from a crowded outfield in Colorado and is one injury-limited season removed from a 24-home run 2014 with the Rockies.
Key losses: The Rays acquired Miller in a deal for pitcher Nate Karns and sent hard-throwing reliever Jake McGee to the Rockies for Dickerson. Karns was surplus in a talented rotation, and McGee was getting expensive for a reliever. The Rays also lost free-agent first baseman-outfielder John Jaso to the Pittsburgh Pirates and infielder Asdrubal Cabrera to the New York Mets.
X-Factor: Pitchers coming back from injury
A pair of left-handed starters with unlimited potential were not themselves last year and the Rays rotation suffered as a result. Drew Smyly suffered a torn labrum in May but returned to make nine starts at the end of the season. He finished with a 3.11 ERA and 77 strikeouts in 662/3 innings. Matt Moore, the top-ranked prospect in baseball entering 2012, came back from Tommy John elbow ligament reconstruction but struggled to a 5.43 ERA and a 1.54WHIP last season. If those two are fully healthy, combined with Cy Young Award contender Chris Archer and solid starter Jake Odorizzi, this rotation could be something special.
Outlook: The Rays regressed a bit in their first season without manager Joe Maddon, but new skipper Kevin Cash seemed to get the most out of his lineup. Dickerson and Pearce should give the Rays a bit more pop, but not enough to do more than compete for one of the wild-card spots.
Toronto Blue Jays
2015 record: 93-69 (first place; lost in ALCS)
Key additions: Toronto made several moves near the trade deadline last season, including trades for shortstop Troy Tulowitzki and 2012 Cy Young winner David Price. Only Tulowitzki returns, and there wasn't much action to speak of during the Blue Jays' offseason. They re-signed pitcher Marco Estrada, and he'll be joined by left-hander J.A. Happ. Happ, who pitched in Toronto from 2012 to 2014, signed a three-year, $36 million contract after he resurrected his career with a 1.85 ERA and 1.03 WHIP with the Pittsburgh Pirates after a July 31 trade from the Seattle Mariners last season.
Key losses: The Blue Jays traded three young pitchers last season for Price, who went 9-1 with a 2.30 ERA for Toronto. But Price, a free agent, signed with Boston, and the Blue Jays rotation will also be without Mark Buehrle. The veteran made 32 starts last season and went 15-8 with a 3.81 ERA, but is unsigned and considering retirement. Off the field, the Jays lost general manager Alex Anthopoulos, who built them into the contender they became in 2015.
X-Factor: Marcus Stroman
Stroman was set to take a big step forward last season before tearing his ACL in spring training. He returned for seven starts, including three in the playoffs. He was much more himself in the initial four starts, posting a 1.67 ERA, but had a 4.19 playoff ERA. Stroman has a career 3.31 ERA in two seasons, and given that his injury was not arm-related, the 24-year-old right-hander is expected to return to form this season. For the Jays' sake he'll have to, as not only will he anchor the rotation in 2016, he'll be the man in Toronto for a long time. The Jays do not have a front-line starter without him.
Outlook: No pitcher will want to face Toronto's power-packed lineup with Tulowitzki, Jose Bautista and Edwin Encarnacion this season, but the rotation is going to be a question mark behind Stroman. Estrada is solid, but Happ needs to carry over the success he had in Pittsburgh to be worth the investment. The Blue Jays will likely return to the playoffs but won't run away with the division again.