A poor start from Yu Darvish hurt the Dodgers early on Friday, and they never mounted a comeback. With the Astros now riding a 2-1 lead and two games left in Houston, the Dodgers are in trouble. In addition to their deficit, a pattern of heavy reliever usage might leave them understaffed in the remaining World Series games.

Darvish didn’t have his best stuff Friday night. Despite impressive fastball velocity, his slider was unusually flat. Houston pounced on the normally dominant ace in the second inning, gaining a four-run lead. From then on, the Dodgers attempted to build a handful of unsuccessful rallies but only managed to score three runs.

Darvish’s bad outing adds to two other shorter-than-necessary starts for Los Angeles and might leave the bullpen tired in the next two pivotal games in Houston. Even if the relievers were fine Friday, the pattern of short starts is a poor omen for the Dodgers.

Of the five teams who leaned on their bullpen most in the series since 2000, three went on to lose, and the Dodgers’ fate is still undecided. Only the 2002 Anaheim Angels came back, and they faced an opponent (in the San Francisco Giants) who employed their relievers even more frequently.

That’s not to say that reliever usage is a death sentence. Oftentimes, it simply reflects poor starting pitching: Each of the teams who used their starters less than the Dodgers saw them give up more than a dozen runs. This underscores how unusual Roberts’s reliever usage has been because his starters, comparatively, have been quite good. Aside from Darvish’s clunker last night, the Dodgers had two of the best starts for their length in World Series history, from Clayton Kershaw and Rich Hill. If Roberts had allowed them to go deeper into games when they were dealing, the bullpen might be fresh now.

Roberts didn’t help matters when he used his bullpen aggressively Friday night, attempting to keep Houston within striking distance. In total, the Dodgers manager called on five different relievers to end the game, and only one — Kenta Maeda — went longer than 2 innings. Combined with the workload from the previous two games, key relievers have been pitching almost as much as the starters. So far, Maeda has pitched 4 innings this series, and Brandon Morrow, the crucial bridge to closer Kenley Jansen, has pitched 2 2/3 innings as well. Jansen himself has pitched 3 full innings.

But as ESPN’s Sam Miller pointed out, if the Dodgers had managed to come back, Roberts’s tactics would have been hailed as strategically brilliant. Like many other postseason managerial moves, the aggressive reliever usage is easy to criticize in hindsight but much harder to argue with in the moment. It might have been a good bet that failed to pay out, but the strategy still leaves the Dodgers depleted of bullpen arms at the time when they need them most. In contrast, Houston manager A.J. Hinch relied on only two pitchers to carry the Astros to victory: starter Lance McCullers and starter-turned-reliever Brad Peacock. Despite running into some high-leverage jams, they managed to hold a powerful Dodgers lineup to only three runs. Like Roberts’ decision, keeping McCullers in the game in the third inning with the bases loaded was a gamble. But Hinch’s call managed to pay off when Dodgers shortstop Corey Seager hit into an uncharacteristic double play.

The Astros’ win leaves them with a 67 percent chance of taking the World Series. That’s far higher than our opening prediction, but it comes almost entirely from the two victories they’ve edged out over the Dodgers. The remaining games are all coin-flip affairs, so the importance of that extra win in an evenly divided series can’t be overstated. That it came down to two managerial decisions that might have gone either way speaks to how balanced this matchup is. Had one or two pitches gone differently, the Dodgers might be in a commanding position right now, instead of fighting to tie the Series.