ESPN Chalk's Joe Peta is sharing his season win total projections for every MLB team, including a reason for optimism and pessimism.
Plus, he recommends an over/under play, or a pass. This is the entry for the Baltimore Orioles.

Baltimore Orioles
Reason for optimism: The Orioles outperform expectations every year under Buck Showalter.
Reason for pessimism: Replacing 40 home runs from one player just can't be done in this era of scoring.
Baltimore fans can be forgiven if they think Vegas has something against them. The Orioles won 93 regular-season games in 2012, the inaugural AL wild-card playoff game against the heavily favored Texas Rangers, and then pushed the Yankees to a deciding fifth game in the ALDS. Oddsmakers scoffed and opened the O's total wins market at 77.5 games for 2013; the Orioles won 85 games. Vegas set the 2014 over/under at 78.5; last season, the Orioles, en route to the AL East crown and an eventual berth in the ALCS, simply won more total games (99) than anyone else in the American League (and only one less than the World Series Champion Giants).
This season's opening total wins market at the influential Las Vegas-based Westgate? 81.5. Vegas remains indifferent to the Orioles' three-year run of success.
I'd love to be outraged on behalf of Baltimore's fans, but it's hard to support that emotion with data.
Ten years ago it wasn't that hard to replace the offensive production of a player who hit 40 home runs, or at least the majority of it; last season, only 11 players hit 30 or more home runs, and only one could muster 40 homers. The bad news for Baltimore is that the one, Nelson Cruz, played for the O's last year but will don Seattle's uniform in 2015. Between the departures of Cruz and Nick Markakis (and their nearly 1,400 plate appearances of .274/.338/.454 production), the Orioles look certain to fall short of their 705 runs scored last year, eighth best in the majors. Granted, they'll get a marginal boost as Manny Machado and Matt Wieters figure to play in more than the 82 and 26 games they appeared in, respectively, in 2014. Travis Snider and Alejandro De Aza, veteran replacements in the lineup for Cruz and Markakis, are hard to get excited about, however. Put it all together and the O's are looking at a year-over-year drop-off somewhere in the area of 35 runs, equating to roughly four wins.
On the other side of the ledger, there is often a hidden element to the success of some playoff teams that doesn't become apparent until the following season. In 2014, the Orioles got 161 starts from the six men who made up their starting rotation. (T.J. McFarland was called upon for a spot start during a period that the Orioles played 10 games in nine days.) That's a huge driver of success because the pitchers, either long relievers or minor leaguers, who fill in for injured starters are typically the very essence of replacement level. To wit: MLB pitchers who started no more than five games in 2014 made a total of 194 starts, and had a whopping weighted-average ERA of 5.76. A team like the 2014 Orioles that virtually eliminates those starts has a big leg up on the rest of the league over the course of a season. The bad news is that type of health almost never is repeated the following year.
Unfortunately for the Orioles, there's another element of pitching that doesn't correlate well from year to year: bullpen ERA. Showalter went to his bullpen often last season (508 IP, tied for eighth in MLB) and was rewarded with a 3.10 ERA, sixth best in the majors. (None of the other teams with ERAs that low used their bullpen for even 500 innings.) In 2013, there were four teams with bullpen ERAs of 3.10 or better -- none of them repeated the feat in 2014. With the exception of Andrew Miller, who came from Boston during the stretch run, all the meaningful contributors to the 2014 bullpen are back, but it's unrealistic to expect the same run suppression this year, especially in the case of Zach Britton and Darren O'Day (145 IP, 1.67 ERA combined).
The Orioles have had a great three-year run, knocking off two playoff opponents while annually exceeding Vegas' preseason expectations. With the current wins market at 83, they may be fairly priced this year, but it's not because oddsmakers have meaningfully raised expectations, it's because last season's 99-win team doesn't project to be as good in 2015.
2015 projection: 80-82 (fourth, AL East)
Bet recommendation: Pass