For Buck Showalter, Don Mattingly and every other manager in these playoffs, it promises to be a most challenging postseason.
This is the first October in which skippers can contest an umpire's call. Nearly everything is subject to replay review, except for balls and strikes, but managers only get one challenge per game if they're wrong.
Based on how they did during the regular season, some teams are better than others at spotting a play that should be reversed.
''I like the job our guy did,'' said Showalter, set to lead Baltimore against Detroit in the AL Division Series. ''You call up, they say, `He missed it,' and you challenge it.''
''It ain't exactly brain surgery,'' he said.
Showalter and the Orioles, who hired a former minor league umpire as their replay coordinator, hit exactly 50 percent this year. They contested 28 calls, 14 got overturned.
The Major League Baseball average was a bit better - 53 percent. Managers made 1,051 challenges and 557 resulted in reversals.
''I mean, I don't know our numbers, but we got a bunch of calls overturned that we wouldn't have had last year,'' Kansas City Royals manager Ned Yost said.
Yost did real well, in fact. He'd gotten it right almost 63 percent of the time going into Tuesday night's thrilling AL wild-card win over Oakland.
St. Louis manager Mike Matheny didn't fare so well at slightly under 39 percent. Of his 31 challenges, only 12 were correct - he tied with Cincinnati manager Bryan Price for the fewest reversals in the majors.
When it came to those oh-so-slow strolls from the dugout onto the diamond, waiting for a bench coach to flash the thumbs-up or thumbs-down, Mattingly nearly matched the MLB average with reversals on 53.8 percent.
Among this year's crop of playoff managers, Washington's Matt Williams was best at 64.5 percent. San Francisco's Bruce Bochy was over 61 percent.
Bob Melvin of the Athletics didn't spend much time trying out the review system. He made the fewest challenges overall in the majors with 26 and was right on 14 of them.
The Royals put Bill Duplissea, a former minor league catcher and previously Kansas City's bullpen catcher, in charge of replays.
''We got a real good video analyst. Very seldom does he ever make a mistake,'' Yost said. ''You know we can't see it, so he's got to almost like suggest what we need to do.''
''And he'll tell us, `Look, this is bang-bang, this is something that I think might be inconclusive,' or you get on there, boom, `Challenge, right off the bat,' you know that he's dead on it.''
The success rates of the other playoff managers: Detroit's Brad Ausmus was 59 percent, Pittsburgh's Clint Hurdle was 57 percent and the Los Angeles Angels' Mike Scioscia was 56 percent.
Showalter said the Orioles changed how they handled replay challenges over the course of the season, but declined to share details of those adjustments.
Their replay guru is Adam Gladstone, who spent four years umpiring in the independent minor leagues and then worked in the front office for an Orioles' affiliate.
''We hired an ex-umpire. I know a lot of guys were hiring ex-players or somebody from the organization. I wanted somebody that really thought about it through an umpire's eyes, and could take the emotion out of it,'' Showalter said.
The best in the big leagues at challenging was New York Yankees manager Joe Girardi, getting reversals on 23 of 28 tries for 82 percent. Chicago Cubs manager Rick Renteria contested the most calls and got the most overturns, going 25 of 56.
''It's a lot better than the NFL's first year, I can tell you that. They had to shut it down for two years,'' Showalter said. ''So we're ahead of the curve where they're concerned.''
AP Sports Writer Jay Cohen and AP freelance writer Ian Harrison contributed to this report.