The first four games of the Western Conference semifinal series between the Houston Rockets and San Antonio Spurs have seen the best and worst of both teams, with each winning twice.

That's why Game 5 of the best-of-seven series, set for Tuesday at the AT&T Center in San Antonio, is so crucial.

Game 6 will be on Thursday in Houston, with a seventh and deciding game -- if necessary -- scheduled for Sunday in San Antonio.

The Rockets, who had looked lost in Game 2 on the road and Game 3 at home, stormed back to claim a 125-104 win in Game 4 on Sunday in Houston to tie the series.

Houston point guard and MVP candidate James Harden scored 28 points and dished out 12 assists in the win. The Rockets' bench stepped up, getting 22 points from guards Eric Gordon and 13 from Lou Williams after the entire reserve unit scored just 10 points in their Game 3 loss.

It helped too that Houston canned 19 3-point shots in the victory Sunday, the second time in the series it had reached that number -- the Rockets had a franchise-high 22 3-pointers in their Game 1 win in San Antonio.

"We did a great job of having patience with our drive-ins," Rockets coach Mike D'Antoni said. "Drive, kick, drive, kick, instead of just throwing up a quick floater, which is kind of what San Antonio wants you to do. We were able to keep moving the ball, or keep moving our people and keep driving until we found the easier shot and it worked."

After recording just four fast-break points in Game 3, the Rockets managed 13 in the first quarter alone in Game 4.

"Our defense was pretty defective," Spurs coach Gregg Popovich said.

Rockets reserve center Nene logged just two minutes before departing with an injury. The team announced on Monday that he would miss the rest of the postseason with a torn left adductor. Nene had averaged 10.8 points and 5.3 rebounds in 19.9 minutes during the playoffs before Sunday's injury.

"Nene is a big part of what we do," Harden said. "Guys have to step up. It's an opportunity for guys who don't play big minutes and for guys who haven't really played and might get some opportunities. Whoever it is, we've got to try to fill that role."

Reserve guard Jonathon Simmons tallied a team-high 17 points for the Spurs in Game 4 while forwards Kawhi Leonard and LaMarcus Aldridge scored 16 apiece and reserve guard Patty Mills added 10 points for San Antonio, which never led in the game.

"Houston made a few adjustments that we just couldn't cope with them on the fly," Mills said. "And it ended up leaving us (playing) soft and exposed our individual (defense), which they took the chances and just drove (on) us."

Although San Antonio would potentially have two of the final three games on its home floor, Spurs venerable guard Manu Ginobili said the team needed to treat Tuesday's contest like it was a Game 7, not a Game 5.

"We had a great opportunity (in Game 4) to go back to San Antonio up 3-1 and in a better situation," Ginobili said. "Now it's 2-2 and we have to go in knowing that every possession is a game-winning possession."

Since moving to the AT&T Center in 2002, the Spurs are 81-28 (.743) in home playoff games, giving them the most such wins by any team in the league since that year.