Maybe the Opening Day adrenaline is gone. Maybe players aren't used to the stress of competing every day. Maybe the MLB grounds crews switched to a new brand of infield dirt. Whatever the reason, injuries have piled up over the last week. Philadelphia has been hit especially hard. The Phillies were already missing Joe Blanton and Brad Lidge, and both Jimmy Rollins and Jayson Werth are limping (although, Werth hopped back into the lineup on Thursday).

Philly fans may be pulling their hair out, but fantasy managers should take a deep breath. These guys will be back, and there are waiver wire fill-ins available.

Jimmy Rollins, SS, Philadelphia Phillies

I'm guessing the phrase "Grade II calf strain" received close to 1 million WebMD hits from the Philadelphia area this week. Rollins went down with the calf problem before the first pitch of the Phillies' 7-4 victory over the Nationals on Monday. Calf strains are generally very painful and the two-to-four week recovery time announced by the Phils is optimistic. Rollins' fantasy owners should plan for him to be out the full four weeks.

Philly's going to roll with Juan Castro while Rollins recovers. Castro's been in the league since 1995, mostly because of his defense. He's a career .230 hitter and is a NL-only league option at best. It's better to look outside the organization to find a fantasy replacement for Rollins. Toronto's Alex Gonzalez is a streaky hitter and he's currently on a hot streak.

The Rollins injury has another fantasy effect. Shane Victorino has jumped into the leadoff spot for the Phils. Victorino will definitely get more plate appearances after moving from seventh to first in the lineup, but he may also get more run scoring and base stealing opportunities. He had his best game of the season on Wednesday, going four-for-five with a home run and five runs batted in from the leadoff spot.

Jayson Werth, OF, Philadelphia Phillies

The circumstances around Werth's hip flexor strain are less severe but more uncertain than Rollins' calf. Werth started Wednesday's game on the bench, but did pinch hit. He returned to the starting lineup on Thursday. It appears that Werth is going to play through the problem, but his fantasy owners should be prepared for occasional days off in the next few weeks.

According to several reports, Lidge is targeting the Phillies next homestand (April 30) for his return. The closer, who is recovering from knee and elbow surgeries, had a good minor league rehab appearance on Wednesday. He pitched a scoreless inning, striking out two, walking one, and allowing no hits. More importantly, his fastball was in the low 90s and his location improved drastically.

Lidge might not walk back into the closer role when he returns. He'll eventually get there, but Ryan Madson might hold onto the ninth inning duties at the beginning of Lidge's return. Madson has two saves in two opportunities.

Ryan Zimmerman, 3B, Washington Nationals

Zimmerman has missed four straight games with a left hamstring injury. The third baseman participated in batting and fielding practice Thursday, and is listed as day-to-day. Zimmerman admits he is unsure of when he'll return, and said after Wednesday's game, "There is no point in pinch-hitting if I can't score on a single." Of course he went on to pinch-hit late in Thursday's game and hit an opposite field homer. The fact that he made an appearance precludes the Nats from making a DL stint retroactively and seems to indicate one won't be necessary.

Alberto Gonzalez has taken Zimmerman's place at third for the Nats, but he's not much of a fantasy option. Hopefully Zimmerman can avoid the DL, but if not, a good option for a mixed league replacement is Ty Wigginton, who is eligible at third base but is playing second for Baltimore while Brian Roberts is on the DL. Wigginton, who is available in most leagues, is batting .333 in limited time this season, is eligible at multiple positions, and hits in a surprisingly potent Baltimore offense.

Brian Roberts, 2B, Baltimore Orioles

As mentioned above, Roberts is out. This time it's due to an abdominal strain, which could be related to the back problems he has been dealing with since spring training. Roberts' back didn't prevent him from missing the beginning of the year, like many thought it would, but it's still not completely healthy. According to the Baltimore Sun, on Monday, Roberts received an epidural shot for the herniated disk in his back.

Roberts is eligible to come off the DL on April 25, but with his back problems and abdominal injury, he could be out longer. As he recovers, Wigginton is an excellent temporary option in both mixed and AL-only leagues.

Miguel Montero, C, Arizona Diamondbacks

Montero's knee injury is old news, but new reports say no ligament damage was found and he underwent surgery to repair his torn meniscus on Thursday. This is excellent news for Montero's fantasy owners, and the catcher should be back before the end of May (four-to-six week recovery time projected by the Diamondbacks).

Montero owners who haven't added Chris Snyder should do so immediately if he is still available. Snyder's not going to continue to hit .300, but he will provide some power. He had 16 home runs in 334 at-bats in 2008 and 13 homers in 326 ABs in 2009.

Aaron Hill, 2B, Toronto Blue Jays

Basically, the Toronto Blue Jays are playing it safe with Hill. This injury is a minor hamstring strain that was originally labeled as hamstring "tightness." It's pretty shocking that Hill landed on the DL, but the move is retroactive to April 6 and it's doubtful that Hill will be out for much longer unless there is some unforeseen setback.

Fantasy owners may be upset that Hill is missing games due to extreme caution, but it's much better than letting him rush back and suffer a worse injury. Hill's replacement, Josh McDonald, has little to no fantasy value.

Chris Young, SP, San Diego Padres

Much like Hill, the Padres claim they are being cautious with Young by placing him on the 15-day DL (retroactive to April 7). Young generated plenty of buzz with his season debut; six scoreless innings with five strikeouts and only one hit.

Right now, Young and the Padres are expecting him to come back immediately after his DL stint. Because it's a shoulder problem, and because of Young's recent injury history (he hasn't pitched more than 110 innings since 2007), I'm personally not quite as optimistic. He's available in most fantasy leagues, but I'd rather take chances with other fantasy options even when he comes back.

Wandy Rodriguez, SP, Houston Astros

Rodriguez has allowed seven runs on 14 hits with six walks and four strikeouts in 10.1 innings so far. He struggled in the spring as well. Following Monday's start against St. Louis, a game in which Rodriguez was pulled after 65 pitches, he said that he felt some soreness in his throwing shoulder.

Rodriguez owners should monitor his next start closely. If he's pulled early or suffers from any type of shoulder pain, he could be headed to the DL.

Ian Kinsler, 2B, Texas Rangers

Kinsler told reporters on Thursday, "As long as I'm playing in October, I'll be fine ... Hopefully it won't last until October. Who knows?"

This was obviously a joke (I hope), but Kinsler is taking his ankle sprain recovery slowly, and probably won't be back until the middle of next week at the earliest. He received a cortisone shot last Friday and has been doing agility drills and taking batting and fielding practice this week.

Joaquin Arias has taken over second base duties and is batting .440 with five runs and a stolen base. With Kinsler's return approaching, Arias has little value. But Kinsler owners in AL-only leagues who haven't found a replacement could rely on the 25-year-old.

There are plenty of players hanging around the training room these days, here are some others.

Atlanta's Chipper Jones is struggling with back spasms and a strained oblique he suffered last Thursday. He's only missed three games and seems determined to play through the pain. ... The Rangers' C.J. Wilson missed his scheduled start Wednesday due to food poisoning. As long as Wilson doesn't go back to that restaurant, he'll be ready to pitch on Friday or Saturday. ... The Seattle Mariners are optimistic that Cliff Lee (abdominal strain) will get his first start in early May. Lee has gone through a few bullpen sessions without pain and will throw a simulated game in the coming days. ... Seattle is not as optimistic about Erik Bedard (shoulder), although they claim he is ahead of schedule. He could be back by the end of May. ... Fernando Rodney will fill in for Angels closer Brian Fuentes (back) while Fuentes is on the DL. But Fuentes' DL stint is retroactive to April 6 and he's expected back next week. ... Kerry Wood (back) will not rush back to help the Cleveland bullpen, but he's recovering quicker than expected and could be back mid-May. ... Daisuke Matsuzaka (neck) threw five scoreless innings in his first rehab start. He struck out three; had good velocity, but he did hit two batters. Matsuzaka is scheduled to throw again on Thursday. ... Blanton is ahead of schedule in his recovery. He could throw a bullpen session on Friday. Cubs starter Ted Lilly (shoulder) will make one more minor league start, Monday, before returning for Chicago.

* All stats up-to-date as of 04/14/10.

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