The Pirates placed Mattson on the 15-day injured list Tuesday with hip inflammation, retroactive to Sunday.
The Pirates outrighted Bethancourt to Triple-A Indianapolis on Monday.
The White Sox activated Murphy (forearm) from the 15-day injured list and optioned him to Triple-A Charlotte on Monday.
O'Hearn (quadriceps) will begin a rehab assignment with Triple-A Indianapolis on Tuesday, Colin Beazley of the Pittsburgh Post-Gazette reports.
Smth (3-1) didn't allow a baserunner across three innings while striking out four to earn the win Sunday against the Twins.
Davis went 1-for-3 with a solo home run Sunday against the Angels.
Peters went 3-for-5 with two doubles, an RBI and three runs scored during Sunday's 10-1 win over the Twins.
Grichuk went 2-for-2 with a solo home run and an additional RBI in the 10-1 win Sunday versus the Twins.
Antonacci went 3-for-4 with three doubles, two RBI and two runs scored Sunday against the Twins.
Teel went 1-for-5 with a three-run home run Sunday against Minnesota.
