(CNN) -- The baseball playoffs were in full gear Thursday, with four potentially pivotal games to get teams one step closer to the World Series.
Two teams moved on and two others stayed alive.
The San Francisco Giants and the Detroit Tigers advanced to their respective league championship series while the Baltimore Orioles and Washington Nationals forced winner-take-all showdowns Friday.
Here's a look at what happened around Major League Baseball on Thursday:
Detroit 6, Oakland 0
Justin Verlander pitched a complete game, allowing only four hits as the Tigers beat the A's in the deciding game of an American League Division Series.
The Tigers scored four times in the top of the seventh to break open a close game. Prince Fielder and Austin Jackson had RBI singles and Detroit scored twice more to take a 6-0 lead.
Verlander, 17-8 during the regular season, threw 122 pitches in going all nine innings.
The Tigers will play the winner of the Baltimore-New York series.
Baltimore 2, New York 1
J.J. Hardy's RBI double in the top of the 13th sent the Orioles and the Yankees to Game 5 of their series.
Manny Machado doubled to lead off the inning and Hardy followed two batters later with a long fly over Yankees outfielder Ichiro Suzuki that made the score 2-1.
Baltimore had jumped to a 1-0 lead in the fifth inning, thanks to a Nate McLouth home run.
But the Yankees tied it up the next frame, when Derek Jeter scored on a ground out by Robinson Cano.
The Orioles' win sets up Friday's showdown. New York manager Joe Girardi has promised that he'll be in the dugout then, as he has been all week, despite the death of his father on Saturday.
Pedro Strop, the Orioles' seventh pitcher of the night, pitched two scoreless innings to earn the win. David Phelps took the loss.
One night after giving up a game-tying home run in the bottom of the ninth, Jim Johnson earned a save.
San Francisco 6, Cincinnati 4
Buster Posey hit a grand slam to lead the San Francisco Giants to a 6-4 National League Division Series-clinching victory Thursday over the Cincinnati Reds.
Brandon Crawford and Angel Pagan also drove in runs as the West champion Giants defeated the Reds three games to two.
The Giants became the first NL team to trail 0-2 in a division series before winning three consecutive games. Under Major League Baseball's new playoff format, San Francisco had to win three road games to do so.
Giants pitcher Matt Cain gave up three runs in 5 2/3 innings to earn the victory. Mat Latos took the loss.
San Francisco next will play the winner of the St. Louis Cardinals-Washington Nationals series.
Washington 2, St. Louis 1
Washington's Jayson Werth hit a home run to lead off the bottom of the ninth, keeping the Nationals alive in their National League Division Series with a victory over the St. Louis Cardinals.
The two teams will play the deciding contest of the five-game series Friday night.
The Nationals used four pitchers who gave up just three hits while striking out 10 batters. Washington's Drew Storen was the winning pitcher, while St. Louis' Lance Lynn was the loser.
Adam LaRoche homered for the Nationals in the second inning, while Carlos Beltran hit a sacrifice fly in the third for the Cardinals' only run.