Chicago hurlers face nice matchups

We'll start today's column with a clarification, since there have been a lot of letters in the mailbag wondering what the difference is between the starting pitcher "Ratings" and the "Rankings" in our master grids in this column on a daily basis. The rating is a measure of the matchup for the day and is based on several factors, including the opponent's lineup strength, lefty-righty splits and ballpark factors. The higher the number, the better a pitcher should do. The ranking uses that as a starting point, but then tweaks it, using the personal opinions of the author -- usually myself or Adam Madison -- as to how well we feel each pitcher will live up to the expectations on this particular day alone.

Of course, regardless of the methodology, it's hard to argue against Roy Halladay each time he takes the mound, even faced with an Albert Pujols-led lineup. After all, odds are he'll give you a complete game and with that strong lineup of the Philadelphia Phillies, there's no reason not to expect a strong likelihood of a victory. As for the rest of the Thursday throwers, here's the complete list:

For starters

Starting pitcher rankings for May 6

Rk.: The author's ranking of that pitcher for that day only. T: Pitcher throws left-handed or right-handed. Opp: The pitcher's opponent for the day. Rating: The starting pitcher's matchup rating -- separate from the author's ranking -- which accounts for past history (three years' worth as well as past 21 days), opponent and ballpark. Ratings range from 1-10, with 10 representing the best possible matchup, statistically speaking, and 1 representing the worst. W-L: Pitcher's win-loss record. ERA: Pitcher's earned run average. WHIP: Pitcher's average number of walks plus hits surrendered per inning.

Selected notes:

• At the top: Dan Haren has been providing his own run support this season, batting .500 (9-for-18). Eventually, the ERA will come around as well and he won't need to help his cause in order to get wins. Randy Wells rounds out our top trio thanks to a 2-0 record and 2.08 ERA against the Pittsburgh Pirates.

• Chicago has two solid starters today. Neither Wells nor John Danks has yet to taste the sting of defeat this season, and we're high on both to keep that streak going. Danks, for his part, has already defeated the Toronto Blue Jays this season, allowing only one earned run in seven innings.

Matt Cain has never lost to the Florida Marlins and has a 2.88 career ERA against them to boot. Similarly, Tim Hudson enjoys the sight of his Thursday opponent. Hudson is 8-1 with a 1.55 ERA when facing the Washington Nationals.

• Rounding out the top 10: The enigma that is Carl Pavano, who has a 5.40 ERA during the past three weeks, squeaks into the mix. As long as he doesn't walk hitters, he's got a good chance of sticking around long enough to get a victory. Wandy Rodriguez is 2-4 with a 5.64 ERA against the Arizona Diamondbacks, so we don't feel confident ranking him any higher than 10th.

• Middle of the road options: Kyle Davies is 0-3 versus the Texas Rangers with a 5.55 ERA, making him a shaky play Thursday. Kyle Lohse has a fairly decent 3.73 ERA against the powerful Phillies and might be able to stun their bats long enough to help out your fantasy team.

• Streamers on alert: Dana Eveland beat the White Sox earlier in 2010, allowing only two runs in six innings. Ryan Rowland-Smith is unbeaten against the Tampa Bay Rays, with a 3.63 ERA, far better than his season-to-date numbers. Dave Bush faces inexperienced John Ely and the Los Angeles Dodgers, which gives him a bit more leeway to work with that 3.98 career ERA against the West Coasters.

• Stay away from ... Scott Olsen and his 6.40 ERA against the Atlanta Braves, Matt Harrison, owner of a 5.40 ERA against the Kansas City Royals, and the clearly "not quite ready to be back in the rotation" Daisuke Matsuzaka all give us the willies.

Now batting

Hitter matchup ratings for May 6

Hitter ratings account for the opposing starting pitcher's past history (three years' worth as well as past 21 days) as well as ballpark factors. "LHB" and "RHB" ratings account only for left- and right-handed batters, respectively. "Steals" is a base stealing matchup rating, which accounts for the opponent's catchers' ability to gun down opposing base stealers.

Hitters' count:

Ryan Theriot, SS, Chicago Cubs: Theriot is a .378 hitter against the Pirates since 2007. Eventually he's going to hit a dry spell, but don't expect it to start anytime this series.

Billy Butler, 1B, Royals: He's got eight hits in the past six games, and with the promotion of Kila Ka'aihue, there's added motivation to keep up the good work. Being 3-for-5 against Matt Harrison also helps.

Alex Rios, OF, White Sox: Rios has nine hits in his past six games and went 1-for-2 the last time he saw Dana Eveland this season. The hits keep on coming!

Jim Thome, 1B, Minnesota Twins: Thome has had hits in six of his past seven games and we've never heard the phrase "but Brad Bergesen is pitching today" used as a justification to be scared.

Matt Diaz, OF, Braves: Diaz has a .440 career batting average against Scott Olsen, including three home runs, and a .960 slugging percentage. If this matchup doesn't get him out of his .180 slump, nothing will.

Ian Kinsler, 2B, Rangers: He's hitting .300 in 20 at-bats since returning from his high ankle sprain and a .333 hitter in 12 at-bats against Kyle Davies. Start him with confidence.

Pitchers' count:

Albert Pujols, 1B, St. Louis Cardinals: In addition to his 0-for-4 lifetime mark against Roy Halladay, the truth is Pujols usually has troubles against the Phillies, batting only .176 against them since 2008.

Lastings Milledge, OF, Pirates: As much as there is a soft spot in my heart for Milledge, I can't get over the .226 batting average and the fact he's starting to get rotated out of the lineup for the Pirates. It's time to let go.

Cristian Guzman, SS, Nationals: Guzman has bracketed a pair of two-hit games around a 2-for-17 streak, and is a .193 career hitter against Tim Hudson.

Mark Reynolds, 3B, Diamondbacks: The strikeouts continue to mount at a record pace for Reynolds, but the batting average hasn't matched his 2009 results. A .167 hitter against Wandy Rodriguez might simply be in need of a day off.

Ichiro Suzuki, OF, Seattle Mariners: Ichiro's slumps are usually few and far between, but he is in the middle of a 2-for-12 run and is only a .222 career hitter against Jeff Niemann.

Pedro Feliz, 3B, Houston Astros: Slumping Feliz, in the midst of a 2-for-19 skid, is a .107 career hitter, or should we say non-hitter, against Dan Haren.

Baseball Challenge Pick of the Day

Carlos Gomez, CF, Brewers: He's back from a knee injury and looks none the worse for wear, going 2-for-4 with an RBI against Clayton Kershaw and the Dodgers on Tuesday. With working wheels and against an inexperienced starter in John Ely, we're hopping on Gomez's back and going along for the ride.


Injury list: Out

Brendan Donnelly, P, Pirates (15-day DL, left oblique)

Rick Ankiel, OF, Royals (15-day DL, right quad)

Tim Byrdak, P, Astros (15-day DL, right hamstring)

Rafael Furcal, SS, Dodgers (15-day DL, left hamstring)

Sean Gallagher, P, San Diego Padres (15-day DL, sprained toe)

Yunel Escobar, SS, Braves (15-day DL, left groin strain)

Curtis Granderson, OF, New York Yankees (15-day DL, strained left groin)

Pat Neshek, P, Twins (15-day DL, finger inflammation)

Injury list: Day-to-day

Gerald Laird, C, Tigers (bruised shin)

Mariano Rivera, P, Yankees (side stiffness)

Dexter Fowler, OF, Colorado Rockies (sprained ankle)

Joe Mauer, C, Twins (bruised heel)

Asdrubal Cabrera, SS, Cleveland Indians (tight left quad)

Andrew McCutchen, OF, Pirates (mild ankle sprain)

Weather concerns

Weatherproof games: Diamondbacks at Astros and Rays at Mariners. As usual, there's a chance of isolated thunderstorms in Miami. Minneapolis also may have some afternoon showers that carry over to game time. If there's going to be a contest that gets hung up by the playing conditions, it's in Boston, where scattered thunderstorms and the threat of lightning may bring out the tarp for extended periods of time.

AJ Mass is a fantasy baseball, football and college basketball analyst for ESPN.com. You can follow AJ on Twitter or e-mail him here.