Balfour, a first-time All-Star, becomes the first Australian born pitcher to ever make an All-Star team and the second Australian player to be selected to play in an All-Star Game; Milwaukee Brewers catcher Dave Nilsson made the All-Star team in 1999.
The 35-year-old has thrived as the Athletics closer this season, posting a 1.67 ERA with 25 saves in 37 2/3 innings. Balfour has fanned 38 batters in 39 appearances, allowing 27 hits and 13 walks.
Colon started for Oakland against the Boston Red Sox on Sunday, making him unavailable to pitch again on Tuesday. The veteran entered with a 12-3 record and a 2.69 ERA in 18 starts.
The Athletics began Sunday with a 55-39 record, good for the second-most wins in the AL. Despite their 1 1/2 game lead over the Texas Rangers in the AL West, Colon and Balfour are the only Athletics players who made the AL All-Star roster.