White Sox starting pitcher Chris Sale made just one mistake Friday against the Athletics, but it was enough to earn him his fourth loss of the season. 

Sale cruised through the first five innings, holding the A's scoreless on two hits, before running into trouble in the sixth. Sale allowed two singles and a walk with one out, before Josh Donaldson put the White Sox behind for good with grand slam. Off the bat, Sale thought the it was flyout that would cost him just one run. 

"It sucks," Sale said to the Chicago Sun-Times. "It shows you how important one pitch can be in a ballgame."

Sale allowed four runs on five hits and two walks in 7 1/3 innings, as his record fell to 5-4. He also struck out six, while throwing 77 of 118 pitches for strikes. 

Sale carries a 2.68 ERA into his next start, Wednesday against the Blue Jays.