The A's are 1 back overall, but tied in the loss column. Who has the edge in terms of remaining schedule? The Rangers. Here's how it looks:
The A's have 45 games left to play. The Rangers have 43. Of the 45 the A's have left, 30 are "overlaps" with Texas. That is, in 30 of their remaining 45 games, the A's either play the Rangers or they play a game against a team against which the Rangers also have a game scheduled. That means the A's have 15 "unique" games and the Rangers have 13.
The A's unique games are as follows:
Indians, 3 games
Orioles, 3 games
Tigers, 4 games
Astros, 1 game
Twins, 4 games
The Rangers unique games are as follows:
Brewers, 2 games
White Sox, 3 games
Pirates, 3 games
Rays, 1 game
Royals, 3 games
Angels, 1 game
In short, the A's have 10 unique tough games left (Indians, Orioles, Tigers) while the Rangers have 4 unique tough games left (Pirates, Rays.) Yes, the Royals have played well recently, but they will very likely be eliminated by the time they play the Rangers. Interestingly, all 10 of the A's tough and unique games come in the next 16 games.
I didn't look at home and away. So far, both the A's and the Rangers have played the same number of away games, with the Rangers therefore having played 2 more games at home.