Pitching wins championships. Everyone has heard that mantra before.
The San Francisco Giants put it to practical use last season by winning their second title in three years on the strength of their arms.
With a crowded field of evenly matched teams chasing a postseason title this year, the team whose unheralded starting pitchers step up to the occasion will walk away victorious.
Obviously, aces such as Clayton Kershaw, Adam Wainwright, Max Scherzer and Justin Verlander go a long way, but the world is already aware of their capabilities. For those squads that must escape the wild-card brawl to make it to the division series, the biggest difference will be made by those starting pitchers who are handed the ball in their respective play-in games.
But what about the division winners that have already secured playoff spots? Some have ridden torrid lineups to success while others have carried forward with a balanced attack, but all of them can use some premium run-prevention from these starters.
Jake Peavy, Boston Red Sox
Jake Peavy has pitched two postseason games during his 12-year career. In those outings, he surrendered a combined 19 hits and 13 earned runs over a combined 9.2 innings.
The Boston Red Sox have scored more runs than any other team in baseball, and they've needed all of them with a rotation lacking a front-line starter. No division leader has given up more runs than the Red Sox, who have no starting pitchers who will instill fear in their opponent for Game 1 of their ALDS.
That's why they'll need a strong stretch from Peavy, who has posted a 3.68 ERA and 1.07 WHIP for the Red Sox since they acquired him from the Chicago White Sox at the July 31 trade deadline.
With Clay Buccholz missing most of the season after starting it so promisingly, Peavy became Boston's second-half ace. With a 7.53 K/9 rate, he's hardly the dominant stud of old who once compiled three straight 200-strikeout seasons with the San Diego Padres. His 8.1 swinging strike percentage stands at a career low as his velocity gradually slips.
Nevertheless, Peavy can reward Boston by giving the Red Sox a few great outings en route to their third World Series title in the past decade.
Jarrod Parker, Oakland Athletics
Jarrod Parker looked like a lost cause in April. Following an excellent rookie campaign, Parker posted a 8.10 ERA through his first five starts, striking out 14 batters and allowing 13 walks.
Now, he's arguably Oakland's most important starter on the mound with a World Series on the line.
Since his horrid start, Parker has registered a 3.14 ERA while harnessing his control. His 4.25 fielding independent pitching mark (FIP) suggests that it wasn't the finest season, but he has been steady as a rock since his blowup April.
Critics of Moneyball always point to Oakland simply riding the success of aces Mark Mulder, Tim Hudson and Barry Zito to playoff appearances.
While the A's have loosened up on their vitriol against stealing bases and now properly factor defense into the equation, they're still chasing market inefficiencies by building a championship contender without any brand-name superstar.
Unless you're buying 40-year reclamation project Bartolo Colon as a legit ace (his 2.64 ERA says so, but his 5.32 K/9 rate leaves room for skepticism), Oakland enters the postseason without a true No. 1.
Parker will have to play a big role in making Billy Beane's stuff work in the postseason.
Kris Medlen, Atlanta Braves
Kris Medlen was baseball's most untouchable pitcher during the waning months of 2012. Once Atlanta moved him into the rotation, he allowed nine runs through 12 starts, recording a 1.29 ERA over that span.
While he hasn't touched that display of near-perfection since, the 27-year-old has again discovered the hot hand down the stretch. Since the beginning of August, he boats a 2.25 ERA with 56 strikeouts and 11 walks over his past 64 innings.
At one point, his season looked like a major letdown, but another commendable year has saved his stat line. He'll never match his 1.57 ERA from last season, but Medlen will gladly take a 3.24 mark alongside a 3.33 K/BB ratio.
Mike Minor and Julio Teheran have garnered most of the attention in Atlanta's rotation this year. Both youngsters are blossoming aces, but Medlen at least got a sip of playoff experience while playing in one of MLB's play-ins last season. He only allowed three St. Louis baserunners over 6.1 innings before the Atlanta's fielding unraveled in a 6-3 loss to the Cardinals.
If Medlen comes back strong, the Braves have as strong of a pitching staff as anyone heading into October.
All advanced statistics are courtesy of FanGraphs.