NEW YORK -- The Boston Red Sox promoted right-hander Sean O'Sullivan from Pawtucket on Friday and demoted Henry Owens to the Triple-A farm team, a day after the left-hander walked six against the Chicago White Sox.
The 28-year-old O'Sullivan was 2-2 with a 3.00 ERA in five starts at Pawtucket. He has an 11-23 record with a 5.95 ERA in 52 starts and 14 relief appearances for the Los Angeles Angels (2009-10), Kansas City (2010-11), San Diego (2013) and Philadelphia.
Red Sox manager John Farrell said the team needed a contingency plan in case Rick Porcello had a short outing against the Yankees on Friday, when rain was forecast. O'Sullivan also could start Tuesday against Oakland.
"When he was in camp, he showed more arm strength than we anticipated. The strike-throwing has been above average for him," Farrell said.
Owens, 23, had a 5.11 ERA and no decisions in three starts for Boston this year, walking 13 in 12 1/3 innings. When he was brought up for the final two months of last season, Owens went 4-4 with a 4.57 ERA in 11 starts.
"Henry needs to go back and look to command his fastball with more consistency," Farrell said.
Asked whether he expected more of Owens, Farrell replied: "Based on what he showed at this level last year, yes."
Boston selected O'Sullivan's contract from Pawtucket and transferred third baseman Pablo Sandoval to the 60-day disabled list. Sandoval will miss the rest of the season following left shoulder surgery Tuesday.