Daisuke Matsuzaka struggled in a rehab start for Triple-A Pawtucket on Saturday, giving up five earned runs and seven hits over 5 1/3 innings of work.

Daisuke struck out five, walked one and hit two batters while throwing just 54 of his 90 pitches for strikes. The Red Sox seem likely to ask him to make one more rehab start. His 30-day rehab window closes May 23.

Daisuke Matsuzaka (elbow) is scheduled to make his next minor league rehab start Saturday with Triple-A Pawtucket.

He's slated to throw around 90 pitches. Dice-K owns a 2.70 ERA and 14/5 K/BB ratio in 13 1/3 innings over his first three rehab starts. His 30-day rehab window expires on May 23, though it's possible the Red Sox could activate him sooner. It's not clear how the roster will shake out, but now is the time to stash him in AL-only leagues.

Daisuke Matsuzaka admits that some days his elbow feels better than others and "right now, I'm hoping when I start, it hits the day I'm feeling good."

Matsuzaka tossed 4 2/3 scoreless innings during his rehab start with Triple-A Pawtucket Monday, allowing two hits and three walks while striking out four. His velocity went down as the game went on, though, so it's clear he's not ready to go deep into games. He's expected to make one more rehab start before possibly joining the Red Sox rotation.

Daisuke Matsuzaka's (elbow) next rehab outing has been pushed to Monday due to expected inclement weather in Toledo, where he had been slated to start as soon as Friday.

No big deal, as the Sox are just playing it safe with the 31-year-old. Matsuzaka has allowed four runs in 8 2/3 innings while striking out 10 and walking two in his two rehab starts to this point. Barring a setback, he could be ready to rejoin the Red Sox as early as mid-May.

Daisuke Matsuzaka (elbow) will make his third rehab start this week at Triple-A Pawtucket.

Dice-K allowed just one run over 4 2/3 innings Saturday at the Double-A level in what was his second rehab outing. If everything continues to go smoothly, he could join the Red Sox rotation in mid-May. The 31-year-old right-hander has made a swift recovery from Tommy John reconstructive elbow surgery.

Daisuke Matsuzaka (elbow) struck out seven and walked two in 4 2/3 innings pitched Saturday for Double-A Portland.

He threw a total of 74 pitches. It was Matsuzaka's second of five rehab starts he'll make this year. The 31-year-old right-hander remains on track to join the Red Sox in late May.

Daisuke Matsuzaka (elbow) is scheduled to make his second rehab start Saturday at Double-A Portland.

Dice-K allowed three runs over four innings Monday in his first minor league rehab game. The 31-year-old right-hander is on track to join the Red Sox in late May.

Daisuke Matsuzaka (elbow) allowed three runs over four innings Monday in his first minor league rehab start with High-A Salem.

Dice-K allowed six hits (including two home runs) while fanning three and walking none. He threw 40 out of 57 pitches for strikes. Matsuzaka is slated to make five starts in the minors, but with his rehab clock officially ticking, he's slated to join the Red Sox by May 23.

The Red Sox believe Daisuke Matsuzaka (elbow) can return to the majors ''on or around'' May 23.

''Daisuke feels really good,'' manager Bobby Valentine said. ''The conversation with him is that he's ready to starting dealing with competition rather than rehabilitation. We will still monitor his pitches. He won't have a 30-pitch inning.'' Matsuzaka will begin a rehab assignment with High-A Salem on Monday. He is scheduled to make five starts in the minors before being cleared to return to the Red Sox.

Daisuke Matsuzaka (elbow) will begin a rehab assignment with High-A Salem Monday.

He'll start off with a pitch count of 75. Dice-K's recovery from Tommy John surgery has gone well to this point, as he hasn't had any setbacks and reportedly was hitting 94 mph during an extended spring training game. It's possible he could be ready to help out the Red Sox by June.

Daisuke Matsuzaka (elbow) tossed three innings Tuesday in an extended spring training game.

Matsuzaka threw 49 pitches, hitting 94 mph with his fastball and reporting no pain or discomfort in his surgically-repaired right elbow. He should return in June.

Nick Cafardo of the Boston Globe reports that Daisuke Matsuzaka (elbow) was "very impressive" during a bullpen session Sunday, "throwing hard and using his secondary pitches."

Most have pegged July as a likely return date for Dice-K, but he's hoping to be back sometime in June. It's encouraging that he's looking good early on in camp, but he obviously still has a long road ahead. Given his performance the last few years even when he was healthy, he shouldn't be counted on for fantasy purposes even if he does make a quicker-than-expected return.

Daisuke Matsuzaka threw changeups Monday for the first time since undergoing Tommy John surgery.

Dice-K had been limited to all-fastball throwing sessions before trainers cleared him for off-speed stuff Monday morning. The Japanese right-hander is not expected to appear in a Grapefruit League game and is doubtful to be ready for major league action before July.

Red Sox manager Bobby Valentine said Monday that Daisuke Matsuzaka (elbow) will not pitch in a Grapefruit League game.

Dice-K is progressing well in his bullpen sessions, but the Red Sox plan to bring him along slowly following Tommy John surgery last June. If all goes well, he should be back around the middle of the season.

Daisuke Matsuzaka threw his first bullpen session Monday since undergoing Tommy John surgery.

"Today is like a warm-up," Matsuzaka said after the short mound workout. "I think I'll throw harder next week." The 31-year-old right-hander underwent the Tommy John reconstructive procedure in June and is unlikely to return to major league action until late in the 2012 season. He's entering the final year of his contract with the Red Sox.

Daisuke Matsuzaka (elbow) is scheduled to throw off a mound shortly after January 1.

Dice-K underwent Tommy John surgery in June and began playing catch last month. The 31-year-old right-hander is making good progress in his rehab, but will likely be sidelined until the mid-point of the 2012 season, which is the final year of his contract with the Red Sox.

Daisuke Matsuzaka (elbow) played catch Monday for the first time since undergoing Tommy John surgery.

Dice-K made 39 throws from a short distance and reported no abnormal pain or discomfort. He's not expected to be healthy again until the middle of 2012.

Red Sox manager Terry Francona confirmed following Friday's game that Daisuke Matsuzaka (elbow) will undergo Tommy John surgery next week.

It was basically a foregone conclusion already, but now it's official. While the exact date hasn't been determined, the surgery will be performed by Dr. Lewis Yocum. Dice-K will likely be sidelined until the mid-point of the 2012 season, which is the final year of his contract with the Red Sox.

Red Sox transferred RHP Daisuke Matsuzaka (elbow) to the 60-day disabled list.

Matsuzaka has very likely thrown his last pitch as a member of the Boston Red Sox, but it's also possible he's thrown his last pitch as a major-leaguer. He should be able to come back fine from his Tommy John operation, but he will be approaching 32 years of age by the time he's finally ready to pitch again, and he may have worn out his welcome in the big leagues.

Tim Brown of Yahoo! Sports has confirmed that Daisuke Matsuzaka will undergo Tommy John surgery.

Matsuzaka and his representatives met with the Red Sox front office on Thursday morning and both sides apparently agreed that undergoing the reconstructive elbow procedure is the best course of cation. Dice-K will be operated on by Dr. Lewis Yocum next week in Los Angeles and probably won't be available to pitch in the majors again until late in the 2012 season. His contract with the Red Sox only runs through the end of 2012.