Matsuzaka is in great shape physically, but still has some work to do from a pitching standpoint, as evidenced when he gave up five runs in a 49-pitch first inning of a Double-A start on Sunday.
"The first inning wasn't too good," said Red Sox manager Terry Francona. "The second inning was actually really good, which was nice, but the first inning was kind of a fiasco. The good news is he feels real healthy."
Dice-K threw a side session at Class A Lowell on Tuesday and with the Minor League season coming to an end, will make what is expected to be his final rehab start on Friday at Triple-A Pawtucket.
Matsuzaka could make his first start back with the Red Sox on Sept. 9 against the Orioles.
Francona wasn't too concerned about Sunday's rocky outing.
"He said he was trying some things. [Maybe he should] try something different," quipped Francona. "Again, it worked in the second inning, but he only had one inning [left] and we weren't comfortable letting him go out any more. Hopefully, he'll have a good side and he'll pitch better the next time out. That's some of the reason for having him face better competition as opposed to Gulf Coast. If you're making some mistakes, you'll pay for it a little bit."
Then there is Lowrie, who has never gotten into any kind of rhythm thanks to left wrist woes.
At the moment, Lowrie, who had surgery in April, is climbing both mental and physical hurdles. He is expected to play at Pawtucket until the International League season comes to an end on Sept. 7.
"When he check swung a couple of times, he's felt kind of like a little bit of a zinger I guess is the best way to put it," said Francona. "And then he has some numbness. That's why we sent him out originally to the doctor ... it's all been kind of to reassure him that this is going to happen, or it can happen, and he's not going to hurt himself.
"It's hard though, he's swinging the bat. If you know you're going to check swing and you're going to go numb ... there's some hurdles physically and mentally and he's just not over them yet. It's kind of obvious when he swings the bat, he's got some bat speed and everything. He certainly doesn't have the strength that he'll have after a good winter just because he hasn't been able to do a lot of things."
The urgency for the Red Sox to get Lowrie back lessened a bit after the club acquired Alex Gonzalez in a trade with the Reds on Aug. 14.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.