SEATTLE -- Brandon Workman or Drake Britton will start Sunday's series finale against the A's, said Red Sox manager John Farrell.
"It would probably come from one of those [two], and as we get through these next couple of days, we'll have a better read on that," Farrell said.
Reliever Steven Wright was also in the mix, but the knuckleballer was removed from contention when he pitched 5 2/3 scoreless innings on Thursday to pick up the win in relief of the struggling Ryan Dempster.
No matter who starts, there will be little, if any, Major League experience on the mound against Oakland's potent lineup. Workman has made one relief appearance for the Red Sox, having been groomed as a starter in Boston's farm system.
Workman made his Major League debut Wednesday, allowing three runs on four hits in two innings. After giving up a home run to the first batter he faced, the right-hander settled in to strike out four.
Britton is currently scheduled to start Sunday for Triple-A Pawtucket. The 24-year old has made one Triple-A start since being promoted from Double-A Portland, lasting 5 1/3 innings while allowing five runs on 10 hits.
The hole in Boston's rotation was formed when No. 4 prospect Allen Webster was sent down Wednesday after surrendering seven runs in just 2 1/3 innings against Seattle on Tuesday. Farrell said that he wanted Webster to improve his fastball consistency in Triple-A.
Buchholz lined up to make Minor League start Sunday
SEATTLE -- Clay Buchholz will likely take another step closer to returning to the Red Sox on Sunday by making a Minor League rehab start.
"Our tentative plan is to have him make a start on Sunday," manager John Farrell said, "but tomorrow's bullpen [session] will give us probably as accurate a read as we can make."
Because of inflammation in the bursa sac of his right shoulder, the All-Star hasn't pitched since June 8. Even so, Buchholz is 9-0 with a 1.71 ERA in 12 starts.
"I think the first time out we're probably going to have him in that 45-50 pitch range. That would be the target," Farrell said. "With that being the case, the next start is going to have to be a progressive start from there so we're not overtaxing the bullpen when he returns."
While he didn't want to put a set number on how many rehab starts Buchholz will have to make, Farrell said Buchholz will have at least two before returning to the Red Sox.
• David Ortiz has 19 home runs. When he gets his 20th, he'll have recorded his 11th 20-homer season with Boston, tied with Dwight Evans and Jim Rice for second most in club history behind Ted Williams' 16.
• The Red Sox scored 11 runs in each of their last two games and now have 11 games with at least 10 runs this year. Their 11 such tilts rank tied for the most in the Majors with the Cardinals.
• The Red Sox's 56 wins are the second most in club history at this time of the season entering play Thursday.
Jacob Thorpe is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.