NEW YORK -- In what was shaping up as a night to forget for the Guardians in Game 1 of the ALCS, the eighth inning provided a reminder of how quickly momentum can shift in the postseason.

After the Yankees were cruising for most of the night as they carried a four-run lead into the top of the eighth, commotion ensued when reliever Tim Hill fielded a throw from right fielder Juan Soto and twice made contact with Brayan Rocchio, who collided with Hill rounding first base and then again when he returned to the bag after his one-out single moved Andrés Giménez to third. Following a huddle by the six umpires on hand, Rocchio was awarded second base due to obstruction.

So what exactly constitutes obstruction? Per MLB Rule 6.01(h): If a play is being made on the obstructed runner, or if the batter-runner is obstructed before he touches first base, the ball is dead and all runners shall advance, without liability to be put out, to the bases they would have reached, in the umpire’s judgment, if there had been no obstruction. The obstructed runner shall be awarded at least one base beyond the base he had last legally touched before the obstruction. Any preceding runners, forced to advance by the award of bases as the penalty for obstruction, shall advance without liability to be put out.

Yankees manager Aaron Boone immediately ran out from the dugout in search of an explanation from crew chief Dan Iassogna.

“Originally, he ruled [Rocchio] not going to second base,” Boone said. “I also wanted to make sure [the ball] didn't hit a runner. I was just getting some clarification. … I've got to still go back and look at it and see exactly, but I was at least satisfied with how they processed it and got together at least.”

Though the Guardians came up short in a 5-2 loss to go down 1-0 in the series, the violation did have some implications by eating into New York’s bullpen. One batter later, Steven Kwan extended his postseason hitting streak to 11 games -- surpassing Kenny Lofton for the longest streak in club history -- by singling home Giménez, leading the Yankees to summon closer Luke Weaver for a five-out save. He was up to the task, squashing a late threat by Cleveland by retiring José Ramírez – who came to the plate with two outs and representing the potential game-tying run – on a groundout to end the eighth. After walking Lane Thomas to start the ninth, he retired the next three in order to preserve the save.

Weaver, who has now appeared in each of New York’s first five postseason games, threw 24 pitches to finish off the victory.

“We’re going to keep battling like we have been all season,” Rocchio said. “We’re not going to give up or give in. We’re going to give the best of ourselves until the end.”