2010 MLB Losses by Team

The Pittsburgh Pirates led all of MLB in losses in 2010, with 105, 4 ahead of the Seattle Mariners. The average across 30 MLB teams is 81.0.

Led all of MLB in 2010 Pittsburgh Pirates 162 games

105 Losses 4 clear of Seattle Mariners

#	Team	League	G	L
1	Pittsburgh Pirates	NL	162	105
2	Seattle Mariners	AL	162	101
3	Arizona Diamondbacks	NL	162	97
4	Baltimore Orioles	AL	162	96
5	Kansas City Royals	AL	162	95
6	Cleveland Indians	AL	162	93
6	Washington Nationals	NL	162	93
8	Chicago Cubs	NL	162	87
9	Houston Astros	NL	162	86
10	Milwaukee Brewers	NL	162	85
11	New York Mets	NL	162	83
12	Florida Marlins	NL	162	82
12	Los Angeles Angels of Anaheim	AL	162	82
12	Los Angeles Dodgers	NL	162	82
15	Detroit Tigers	AL	162	81
15	Oakland Athletics	AL	162	81
	MLB average			81.0
17	Colorado Rockies	NL	162	79
18	Toronto Blue Jays	AL	162	77
19	St. Louis Cardinals	NL	162	76
20	Chicago White Sox	AL	162	74
21	Boston Red Sox	AL	162	73
22	San Diego Padres	NL	162	72
22	Texas Rangers	AL	162	72
24	Atlanta Braves	NL	162	71
24	Cincinnati Reds	NL	162	71
26	San Francisco Giants	NL	162	70
27	Minnesota Twins	AL	162	68
28	New York Yankees	AL	162	67
29	Tampa Bay Rays	AL	162	66
30	Philadelphia Phillies	NL	162	65

A team's total is its players' numbers for the club added up, so a player traded mid-season counts for each team only what he did there. Rates such as ERA and batting average are worked out from the team's summed totals, not averaged across players.