Just how bad has the American League West been this season?On Friday, the Athletics fired longtime general manager David Forst, following news in June that the Angels dismissed their GM, Perry Minasian. This week, the three teams with a realistic chance of winning the division — the Astros, Rangers and Mariners — did little to improve their rosters significantly at the trade deadline.What’s left is a division that is on course to make history. Not the good kind.Never has a division featured five teams with negative run differentials, a solid indicator for broadly assessing whether a team is actually good. This year’s American League West may be the first to finish 0-for-5.At the start of play Friday, all five teams were comfortably in the red, with the Mariners representing the class of the field at minus-14. The five teams have been outscored by 305 combined runs, a big part of that being the pitching woes of the A’s and their league-worst run differential of minus-157.

AL West standings (entering Friday) TeamsW-LGBDIFFAstros59-57—-25Rangers57-581.5-33Mariners56-603-14Athletics45-7013.5-157Angels44-7114.5-76

That whopping run-differential disparity comes despite the fact the division is home to perhaps the best player in the American League, the Astros’ Yordan Alvarez. Alvarez leads baseball with 35 home runs and is atop all three AL Triple Crown categories by a considerable margin.If Alvarez does win the Triple Crown, he will be the first left-handed hitter to capture it since Carl Yastrzemski in 1967 — history that doesn’t fit within this disastrous division.Baseball’s current divisional setup began in 2013, when the Astros moved from the NL Central to the AL West. The move brought every division to five teams. Only seven times has any division featured one team that scored more runs than it allowed. Never has there been zero.