Here are five matchups to watch in the National League Division Series:
Josh Hader vs. the playoff workload
The credo of the relief pitcher is to never admit weariness, to always take the ball when asked. But Hader's relationship with Brewers pitching coach Derek Johnson and manager Craig Counsell is more proactive than that, more open and honest, because they all understand and acknowledge the obvious: He's a better pitcher when he has more rest. His stuff is better. And as he demonstrated again against the Cubs in Game No. 163, when he threw his four fastest pitches of the season, Hader can be the best bullpen weapon in baseball when he's at his best.
The challenge for Counsell is to find proper rest for Hader within the more intense circumstances of the playoffs. The built-in off days for every series will help, but Counsell will have to continue to be disciplined, as he was all year, in his use of the left-hander. Hader made just 55 appearances during the season, with the vast majority in high-leverage moments.
Two years ago, Andrew Miller dominated the postseason and propelled the Indians into the World Series. Indians manager Terry Francona used him liberally -- in any close game, and not just when Cleveland was ahead. There will be situations in which Counsell might be tempted to call on Hader, because in October, every situation seems like a high-leverage moment.
Rockies manager Bud Black vs. presumed MVP Christian Yelich
Yelich is the hottest hitter in baseball right now, and in a game against the Cardinals in the last week of the regular season, St. Louis pitched around him repeatedly, walking him five times -- and he scored both runs in a 2-1 Milwaukee win. In Game 163 on Monday, the Cubs took a more conventional approach and pitched to Yelich with a runner in scoring position and first base open, and Yelich answered with a run-scoring single to give the Brewers a lead.
Now it will be up to Black to decide whether to go after Yelich or to veer around him. Something to remember: The Rockies issued the fewest intentional walks in the National League this year, just 24.
Ronald Acuna Jr. and Ozzie Albies vs. October heart rate
The Braves' left fielder and second baseman are two of the game's most dynamic young players, combining for 125 extra-base hits, 30 steals and 183 runs. But baseball has a long tradition of young stars being overwhelmed by adrenaline in their first appearances on the big stage, and high-energy players like Acuna and Albies are probably even more susceptible. They are not patient hitters -- Albies averaged 3.49 pitches per plate appearance, fourth lowest in the NL -- and Hyun-Jin Ryu and Clayton Kershaw, the Dodgers' starters in Game 1 and Game 2, will probably endeavor to use that trait against them and coax them into swinging at pitches out of the strike zone.
Kenley Jansen vs. his stuff
Jansen is not the same overpowering closer he was a couple of years ago, a rival evaluator said midway through this season. The L.A. closer once consistently beat hitters with his cut fastball, but that's probably not possible anymore. "The days when he can throw the same pitch in the same spot are over," the evaluator said.
The Jansen of 2018 could require more rest, with postseason appearances limited to three to five outs, and he'll probably have to move the ball around against hitters, pitching to weaknesses rather than just crushing hitters with what he does well. Jansen had never allowed more than six homers in any season before 2018, but this year, he allowed 13.
Opponents' slugging percentage vs. Jansen
2013: .273
2014: .333
2015: .298
2016: .252
2017: .270
2018: .383
Atlanta's starting pitchers vs. the weight of responsibility
Because the Braves don't have a lockdown bullpen, they'll have to rely on their rotation to carry them deep into games, and it's possible that that formula could work for Brian Snitker. But given the depth of the Dodgers' lineup and the emergence of Walker Buehler as a star-level pitcher, Mike Foltynewicz will work with little margin for error in Game 1 on Thursday; Anibal Sanchez, now 34, has to be competitive in his start against Clayton Kershaw in Game 2; whoever Snitker aligns for Game 3 will probably have to match Buehler's work, zero-for-zero.
The Braves appear to have a great and promising future, largely because of what that their young starters might accomplish collectively. But if Atlanta is to surpass expectations in this postseason, that full maturation must happen immediately.