James McDonald has an 8.71 ERA in the second half of the season.
Several National League teams have exceeded expectations through the first four-and-a-half months of the season. Excellent performances from breakout or established stars fueled much of that success for baseball's first-half surprises.
But in the season's second half, a few of those players have regressed to the point where they could end up costing their teams a playoff spot.
That doesn't apply to every player on this week's list, however. We have a shortstop who once again showed a lapse in focus, a pitcher returning from the disabled list and a newbie catcher who could give his team something to look forward to in the future.
Actually, some improvement from each of these names could restore or instill hope for their respective teams. Here are five NL players who need to have a good week.
New York Mets manager Terry Collins is doing his best impersonation of Kevin Bacon in Animal House when it comes to the health of Johan Santana.
In his past four starts, Santana has allowed 27 runs and 36 hits over 14 innings. That's sent his ERA skyrocketing from 2.76 to 4.58. He only has 14 strikeouts during that four-game span.
Since throwing a no-hitter on June 1, Santana's ERA is 7.98 in nine starts.
Yet, despite what seems to be evidence to the contrary, Collins insists that his star left-hander is healthy.
After Santana's eight-run, 1.1 inning implosion on Saturday, Aug. 11, the Mets skipper told reporters (among them the Star-Ledger's Andy McCullough) that the team had no concerns about Santana's shoulder or ankle and didn't believe he came back from the disabled list too soon.
Santana is scheduled to start Friday, Aug. 17, against the Washington Nationals. He'll get an extra day of rest because the Mets have an off-day on Monday. Will that be enough for him to make a respectable effort against the NL East leader?
The second half of the season has not gone well for Chicago Cubs shortstop Starlin Castro. He's batting .214/.267/.384 in 120 plate appearances.
The Cubs can probably deal with that as long as Castro plays good defense at shortstop. But yet again, the 22-year-old spaced out in the field and made an embarrassing mental mistake that raises questions about his ability to focus.
As ESPN Chicago's Doug Padilla wrote, Castro made two glaring mistakes in Friday's (Aug. 10) game against the Cincinnati Reds.
The worst was getting thrown out on an attempted steal of second base after Castro lost track of where the ball was hit. Castro was tagged out at third base.
Earlier in the game, Castro committed an error on a routine slow-roller to shortstop.
Add those two gaffes to the other mental mishaps he's committed this season, and it's easy to see why the Cubs are frustrated with their young star.
That compelled both Cubs manager Dale Sveum and teammate Alfonso Soriano to have words with Castro, basically telling him that he needs to concentrate more during the game and prepare both mentally and physically.
Castro wasn't benched for the next game, though Sveum reportedly considered it.
Along with pitcher Jacob Turner, one of the key pieces the Miami Marlins received from the Detroit Tigers in return for Omar Infante and Anibal Sanchez was catcher Rob Brantly.
The future is now for Brantly, as the Marlins called him up after Sunday's (Aug. 12) game. Marlins manager Ozzie Guillen told the Miami Herald's Clark Spencer that Brantly is going to play, so he'll likely platoon with incumbent catcher John Buck. The plan is for the right-handed batting Buck to play against left-handers, so he'll play on Monday (Aug. 13) against Cole Hamels and the Philadelphia Phillies.
Brantly has been extremely impressive with the bat since coming over from the Tigers organization. In 54 plate appearances with the Marlins' Triple-A New Orleans affiliate, he batted .365/.389/.558 with two home runs and 11 RBI.
It's probably a bit unfair to say Brantly has to have a good week right away, but as mentioned, Guillen intends to play him. If Brantly makes a decent showing, perhaps the Marlins will consider Buck expendable and can trade him and the $6 million he's owed next season.
Getting some immediate return on one of the team's disheartening midseason sell-off deals might give some encouragement to soured Marlins fans too.
Pitching in a rehab start for Triple-A Gwinnett on Sunday, Aug. 12, Tommy Hanson threw five scoreless innings and allowed only three hits. He also struck out five batters and walked two.
Hanson is recovering from a lower back strain, and his return gives the Atlanta Braves a nice problem to deal with, but a tough dilemma for manager Fredi Gonzalez and general manager Frank Wren to solve.
As the Atlanta Journal Constitution's David O'Brien writes, the Braves could go with a six-man rotation since the team doesn't have a day off until Aug. 30. But disrupting each starting pitcher's routine is obviously a concern as well.
Kris Medlen was moved to the rotation from the bullpen, so he would seem to be a logical candidate to go back. But he's been outstanding in three starts, allowing a total of three earned runs over 16.2 innings.
However, Hanson had struggled with consistency before going on the DL—perhaps due to his back injury—so maybe it would be a good idea to pitch him out of the bullpen and make sure he's at full strength.
Giving someone a rest in favor of Hanson is one thing. But if he struggles in his next one or two starts, the Braves might feel they have no choice but to remove him from the rotation through the final weeks of the regular season.
James McDonald was a key part of the Pittsburgh Pirates' early-season success and surge to contention in the AL Central.
For the first half of the season, he was an NL Cy Young Award candidate, compiling a 9-7 record, 2.37 ERA and 100 strikeouts in 110 innings. McDonald also had an 0.97 WHIP, and opposing batters managed a .196 average against him.
Since the All-Star break, however, it's been rough going for the 27-year-old left-hander. McDonald has allowed four runs or more in six straight starts. In the second half, he has a 1-2 record and 8.71 ERA in six appearances. He's struck out 26 batters and walked 21 in 31 innings.
Besides those walks, McDonald has also been prone to giving up home runs. He served up seven in 110 innings during the first half of the season, but has allowed eight balls to leave the park during his 31 second-half innings.
McDonald gave the Pirates a strong No. 2 pitcher behind A.J. Burnett at the top of their starting rotation. Actually, for most of the first half, McDonald was the better pitcher.
But with McDonald in free fall now, the Pirates are having difficulty winning consistently and it's costing them in the NL Central. As of Aug. 13, the Bucs are 4.5 games behind the Cincinnati Reds, though they still have a 2.5-game lead for one of the NL's wild card playoff spots.
At the risk of making a totally obvious statement, Pittsburgh needs McDonald to return to something close to that first-half form if it's going to make a playoff run and end their 20-year postseason drought.
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