MILWAUKEE -- He will take the mound on Sunday in the most pressurized game of his career, during a time when some of the biggest questions about him as a pitcher exist. This is the world Shaun Marcum and the Milwaukee Brewers are straddling now that they are one loss away from going home for the winter.
"It's exciting," Marcum said. "It's definitely the biggest game of my career."
Marcum will start Game 6 of the National League Championship Series hoping to help prevent the St. Louis Cardinals from advancing to the World Series. The Brewers are down 3-2 in the series, and Marcum, who has a 12.46 ERA this postseason and has seemingly strayed away from his best pitch, the changeup, is tasked with finding his way through this elimination game.
"I've been in the American League East, so I'm used to getting beat up," said Marcum, who went to the Brewers this past winter in a trade from the Blue Jays. "It's just something that happens -- baseball is a weird game. ... My confidence is still as high as it's ever been."
One could understand if it wasn't. After all, the last six weeks have been mostly unkind to Marcum, who gave up 18 earned runs over his final four starts of the season, and who still hasn't looked right this postseason. His manager, Ron Roenicke, attributes some of that to Marcum getting away from his game plan, and some of it to being unlucky.
"I think early in the season, his stuff was maybe a little crisper," Roenicke said. "Maybe they weren't quite getting that bloop hit, or hitting it to where we can catch it, or a swing and a miss. I still think he's throwing well. I don't think he's as bad as what his numbers have been."
His numbers have not been pretty, especially against the Cardinals. In Game 2, the Cardinals battered Marcum for five runs and seven hits in four innings. The Brewers eventually lost that game, 12-3. In five starts overall against the Cardinals this season, Marcum is 1-2 with a 5.10 ERA.
"The Cardinals may just have his number," said one scout who's covered this series. "They may understand what he's doing; these teams know each other so well."
Before this series, however, the Cardinals' hottest hitters had little success against Marcum. Lance Berkman was 1-for-15 lifetime against Marcum; David Freese was 1-for-7 and Albert Pujols was 1-for-9 with three walks. While all the sample sizes are small, it was guys like Nick Punto (.356, 4-for-11) and Gerald Laird (.333, 4-for-12) who had seen a small measure of success. Matt Holliday also had fared well, the lone player to homer off Marcum.
But all of those numbers were before Game 2, in which Pujols, in particular, teed off on Marcum, hitting a two-run homer and a two-run double as part of his 4-for-5, five-RBI day.
The scout said Marcum, who throws multiple pitches, none of them hard, relies on command. So when he's missed, the Cardinals have taken advantage.
"His changeup is in around 81 [mph] and his fastball [tops out at] 88, so there's not as big of a separation [in velocity]," the scout said.
But teammate Randy Wolf says Marcum actually throws two changeups, one around 81 mph and the other around 73. For whatever reason, Marcum mostly abandoned those and his curveball in Game 2, and Wolf thinks they are critical for his success on Sunday.
"Shaun's one of those guys who's really good at messing with guys' bat speeds," Wolf said. "And putting [something] on a pitch and taking off. I think that's the one thing that is his strength. He's not a hard thrower; he's great at mixing speeds. When he does that, he's incredible to watch."
Interestingly, Marcum himself said the most important pitch for him to locate is his fastball, and lately he's had trouble with it.
"For me that is the one pitch that I have to use or I'm not going to be in the game that long," he said.
His recent downward spiral has caused some to think he could be hurt, but perhaps he is just wearing down. He pitched a career-high 200 2/3 innings over 33 starts during the regular season. He is two years removed from Tommy John surgery, and in back-to-back years he's thrown a career-high 20 quality starts. But Marcum insisted on Saturday that physically he is fine.
"I feel great, actually," he said. "Arm feels good, body feels good. It's just matter of going out there and locating and keeping the ball down, throwing strikes to stay ahead of the hitters."
He will have one more chance to do it. If he struggles early, Roenicke said he has a plan in place with his bullpen, but he wouldn't reveal it to reporters Saturday. Chris Narveson is thought to be one of the first choices to be a long man, and Narveson said he'd be ready when called upon. But Yovani Gallardo will not be pitching on Sunday, Roenicke said.
Of course, Roenicke is hoping a backup plan will not be necessary. As of now, perhaps one of the lasting images of this postseason is Marcum tossing his glove in the air like pizza dough after giving up a grand slam to the Diamondbacks in the NLDS. A looping gif of his toss quickly made its way around the Internet, seen by most through the prism of humor.
While Marcum even said afterward he was unaware of what he had done, it doesn't negate that it came at an awful moment, one of many for Marcum recently. With his adjusted game plan, which neither he, nor Roenicke, nor pitching coach Rick Kranitz revealed, the Brewers' collective hope is he will come out on Sunday and mix his pitches, command the zone and prevent St. Louis from clinching, here at their home, on their mound at Miller Park. What Marcum hopes to be is what he was for the Brewers the majority of the year: one of their best pitchers.
Amy K. Nelson is a staff writer for ESPN.com. She can be reached at Amy.K.Nelson@espn.com.