Now that your fantasy baseball drafts are complete and Opening Day is finally here, you're ready to see those hours of tireless research pay off. But alas, much more work remains.

Whether your league allows weekly or daily lineup changes, remember one bit of solid advice: Play your studs. It makes little sense to draft Ryan Zimmerman in the third round and then sit him because he faces the likes of Roy Halladay and Johan Santana this week (for the record, Zimmerman is 1-for-6 with an RBI in his career against Halladay; 5-for-16 with 4 RBI versus Santana).

Also, don't bench an aging veteran like Carlos Lee or Manny Ramirez because he has less upside than Jason Heyworth or Kyle Blanks. The youngsters will get their chance, but they need to wait their turn.

But chances are, you don't have a stud everywhere. If you're weak at a certain position and need to form a platoon, here are a few impact players worth starting in mixed leagues during Week 1:

Mike Napoli, C, Angels (vs. MIN (4), vs. OAK (3)): Despite sharing catching duties with Jeff Mathis last season, Napoli raked (.272, 20 HR, 56 RBI in 114 games). Plus, Mathis hurt his hand this spring.

Nick Johnson, 1B, Yankees (@BOS (3), @TB (3)): Optimistically, I can see him staying healthy as the DH and prospering in the second hole. Pessimistically, I probably won't be saying this in Week 11.

Rickie Weeks, 2B, Brewers (vs. COL (3), vs. STL (3)): Weeks can produce when healthy, and he's hitting in front of run-producing machines Ryan Braun and Prince Fielder.

Ian Desmond, SS, Nationals (vs. PHI (3), @NYM (3)): Desmond beat out veteran Christian Guzman for the shortstop job this spring and batted .354 in 55 games last season at AAA-Syracuse.

Troy Glaus, 3B, Braves (vs. CHC (3), @SF (3)): Glaus is another health risk, but he's worth milking as long as he is in the lineup. He's probably not eligible at 1B yet, but he'll be serviceable among a weak 3B crop.

Carlos Gonzalez, OF, Rockies (@MIL (3), SD (3)): One of the top sleeper candidates this season, Gonzalez is projected to lead off for the Rockies.

Jason Kubel, OF, Twins (@LAA (4), @CWS (3)): Kubel was Minnesota's quiet thumper last year (.300, 28 HR, 103 RBI) and hit four homers this spring.

Edwin Jackson, SP, Diamondbacks (vs. SD, vs. PIT (two starts)): Jackson's career in Arizona begins with two starts at home against two weak offenses.

Randy Wolf, SP, Brewers (vs. COL, vs. STL (two starts)): Wolf is a solid start this week despite a tough second matchup against Chris Carpenter.

Mark Buerhle, SP, White Sox (vs. CLE, vs. MIN (two starts)): I threw my first perfect game last year with Buerhle (OK, I didn't do anything except start him and earn a lot of points).

Franklin Morales, RP, Rockies (@MIL (3), SD (3)): A decent fill-in option while closer Huston Street is injured, Morales went 7-for-7 in save opportunities last season, albeit with a 4.50 ERA.

Here's who you should consider sitting in most mixed leagues:

Buster Posey, C, Grizzlies (@REN (4)): Just wanted to make sure you knew baseball's next great catcher was sent down to Fresno, and that you can't accumulate fantasy points from players in the minors.

Derrek Lee, 1B, Cubs (@ATL (3), @CIN (3)): The 1B position is a deep one this year and Lee struggled mightily during the spring (.175 in 40 AB).

Ian Stewart, 2B, Rockies (@MIL (3), SD (3)): He strikes out too much and faces three lefties this week.

Rafael Furcal, SS, Dodgers (@PIT (3), @FLA (3)): A major disappointment last season, Furcal only batted .269 with 12 steals and 47 RBIs.

Brandon Wood, 3B, Angels (vs. MIN (4), vs. OAK (3)): The former prospect won the everyday job in Anaheim, but has yet to prove he's starting material in fantasy circles.

Corey Hart, OF Brewers (vs. COL (3), vs. STL (3)): Hart will lose playing time to 39-year old Jim Edmonds and could be trade bait if the Brewers sign Jermaine Dye.

Jeff Francouer, OF, Mets (vs. FLA (3), vs. WAS (3)): Frenchy has fallen off big time since being touted on the cover of Sports Illustrated in 2005 as "The Natural."

Nate McClouth, OF, Braves (vs. CHC (3), @SF (3)): A miserable spring (.118 in 51 AB, 3 SB) and a hamstring pull make him undesirable for opening week.

John Lannan, SP, Nationals (vs. PHI, @ NYM (two starts)): He gets two starts this week, but they come against Halladay and Santana.

Roy Oswalt, SP, Astros (vs. SF, vs. PHI (two starts)): The former fantasy stud is banged up. Plus, how many wins can you expect against Tim Lincecum and Halladay?

Jake Westbrook, SP, Indians (@CHW, @DET (two starts)): Let's wait and see on this Tommy John patient, who hasn't pitched in a regular-season game since May 2008.

Billy Wagner, RP, Braves (vs. FLA (3), vs. WAS (3)): Also recovering from TJ surgery, Wagner had a rough spring (5.40 ERA in 10 appearances). He's more likely to give you an ulcer than a save.

Finally, my condolences to your fantasy team if it's seeing more red crosses than upward arrows. Perhaps you assembled a killer squad for September but that is currently limping to the starting line. Make sure your starters don't look like a wounded All-Star team:

Yadier Molina, C, Cardinals (oblique); Lance Berkman, 1B, Astros (knee); Ian Kinsler, 2B, Rangers (ankle); Jose Reyes, SS, Mets (thyroid); Alex Gordon, 3B, Royals (thumb); Carlos Beltran, OF, Mets (knee); Coco Crisp, OF, Athletics (finger); Cliff Lee, SP, Mariners (suspension, abdominal); Brandon Webb, SP, Diamondbacks (shoulder); Daisuke Matsusaka, SP, Red Sox (neck); Ted Lilly, SP, Cubs (shoulder); Erik Bedard, SP, Mariners (shoulder); Huston Street, RP, Rockies (shoulder); Brad Lidge, RP, Astros (knee)

More DL casualties: Russell Branyan, 1B, Mariners (back); Daniel Murphy, 1B, Mets (knee); Freddy Sanchez, 2B, Giants (shoulder, knee); Joe Blanton, SP, Phillies (oblique); Scott Kazmir, SP, Angels (knee); Jeff Francis, SP, Rockies (shoulder); Gil Meche, SP, Royals (shoulder); Kerry Wood, RP, Indians (back).

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