Rockets head coach Mike D’Antoni pulled out all the stops to even Houston’s series against the Warriors at 2-2 on Tuesday. He cut his rotation to seven players, with the seventh (Gerald Green) playing only 12 minutes. There’s no margin for error in a series between two elite teams that can attack weak spots anywhere in a lineup. The Rockets and the Warriors have been taking turns picking on each other’s worst players, so the obvious adjustment is to not play them. As the circle of trust gets smaller, the more avoiding fatigue and injury becomes crucial. The Rockets have turned the Western Conference finals into a war of attrition.

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D’Antoni knew what his best lineup was by the end of their 127-105 win in Game 2. Clint Capela had been dominant in the first two rounds, but Golden State’s all-switching defense erased any open lanes to the rim, turning him into a nonfactor on offense. Luc Mbah a Moute, meanwhile, is still dealing with the lingering effects of a shoulder injury, shooting only 6-for-19 in the restricted area in the playoffs. With those two struggling, Houston’s best five-man unit against Golden State features James Harden and Chris Paul flanked by a third scorer (Eric Gordon), a 3-and-D forward (Trevor Ariza), and a small-ball 5 (P.J. Tucker).

The lineup numbers are striking. Houston’s starters (Harden, Paul, Ariza, Tucker, and Capela) have a net rating of minus-24.7 in 43 minutes in the series. Replace Capela with Gordon and that number shoots up to plus-7.4 in 38 minutes. The problem for D’Antoni in Houston’s 126-85 loss in Game 3 was that giving that lineup big minutes would have thrown a curveball into his normal rotation pattern. He likes to stagger Paul’s and Harden’s minutes so that one of the two is always in, which means they normally play together only at the start of the first quarter and end of the second. So when he started Capela, it meant he couldn’t get to his best lineup until 4:58 left in the second quarter, when the game was already out of hand.

The fix in their 95-92 win in Game 4 was simple: don’t rest anyone. Harden played 43 minutes, and Paul played 41 and a half. The result was more opportunities for Harden, Paul, Gordon, Ariza, and Tucker to share the floor. They played more minutes together in Game 4 (20) than they have in the rest of the series combined (18). A coach is like a jockey on a racehorse: He has to start the finishing kick at exactly the right time so he won’t run out of steam at the end. Abandon the rotation pattern too early and the players could buckle from fatigue. D’Antoni waited as long as he could to throw caution to the wind and go for it.

A playoff series is often described as a heavyweight fight, with the two teams feeling each other out for the first couple of games. Boxers generally don’t come out swinging in the first round because it’s important to conserve energy for the final blows. It’s the same reason why guys like David West, Nene, and Ryan Anderson all played in Game 1, even though neither team was likely to stay big for long. They needed to pace themselves before the intensity ratcheted up.

The concern, especially with older players, is keeping their minutes down as long as possible to keep them fresh. Paul was hobbling around earlier in the series, although he had 27 points and four assists on 10-of-20 shooting in Game 4. The big loss for Golden State was Andre Iguodala, who sat out with left knee soreness after tweaking it in the second half of Game 3. Paul, 33, and Iguodala, 34, are the oldest players in their respective rotations. And while Iguodala is the only member of the Hamptons Five who wasn’t an All-Star this season, his absence was felt on Tuesday. He does all the little things that make that group click.

Iguodala is one of Golden State’s best perimeter defenders and playmakers, and he has the highest playoff net rating (plus-13.6 in 357 minutes) of any player in their rotation. Harden, Paul, and Gordon are a combined 6-of-19 against him, plus he had five assists and five steals in the first three games. The biggest blow in Game 4, though, is the way his absence threw off Golden State head coach Steve Kerr’s rotation. Iguodala had been averaging 27.3 minutes per game in the series, and he helped anchor the defense when Draymond Green was out. Kerr kept one of the two in for almost all of the competitive portions of games 1 through 3.

Kerr replaced Iguodala with Kevon Looney in Game 4, but the coaching staff never seemed comfortable with what moves to make from there. Draymond played 45 minutes and didn’t come out in the second half. All four of Golden State’s All-Stars played the whole third quarter. Looney and rookie Jordan Bell struggled in Iguodala’s role as the fifth option, allowing the Rockets to shrink the floor and tighten their defense on the Warriors’ main options. There just weren’t many lineup combinations that made sense for Kerr, since he didn’t want to play Looney and Bell together, or dig into his uninspiring perimeter depth and play Nick Young or Quinn Cook more.

The big question for Golden State is how much it can count on Iguodala. His X-rays were negative, but there’s no way to know how his body will respond to the time off. The obvious adjustment if Iguodala returns is to go to a seven-man rotation with Looney and Shaun Livingston off the bench. The level of play in this series is so high that it’s hard to justify keeping even decent players out there for any amount of time. Young killed the Warriors on Tuesday: He had two points on 1-of-3 shooting in 14 minutes, with a plus-minus of minus-14. He took bad shots, committed silly fouls, and missed rotations, and Houston made him pay for it. Gerald Green, who played only 12 minutes, presented the Rockets with the same issue.

The question for both coaches is whether they can buy any time with fringe players in the next few games. The conference finals are hitting the stretch run. There’s only one day between each of games 4 through 7, and the teams will be crisscrossing the country on those days. D’Antoni and Kerr have to find any edge they can to keep their players fresh. Home-court advantage could be crucial. Playoff games can be swung by unlikely names, and the Rockets have options (Mbah a Moute, Anderson, Joe Johnson) who might be energized by their crowd.

Game 4 felt like the last games in the 2016 Finals between Golden State and Cleveland, the last time the Warriors were pushed. As with Kerr and Tyronn Lue before, both the Warriors and Rockets coaching staffs cycled through all their adjustments, and knew exactly where they wanted to attack. The shortened rotations wore out the players still standing. They seemed to stop moving and settle for more isolations as the series progressed. Each team knew the other’s plays intimately, while the referees allowed more contact off the ball. All of the cutting Golden State is known for ground to a halt, just like it did in 2016, and it was forced to play Houston’s preferred style of dueling isolations.

The difference for the Warriors is Kevin Durant, who gives them a significantly bigger margin for error. Curry and Iguodala were both hurting by the end of the 2016 Finals, leaving Klay Thompson and Draymond to do the heavy lifting on offense. Durant is averaging 31.8 points a game on 48.9 percent shooting against the Rockets, and his always-present ability to create a good look helps them survive off nights from either Splash Brother. The Rockets don’t have that luxury. Harden, Paul, and Gordon all have to be rolling. Paul and Gordon outscored Curry and Thompson in their two wins. They were outscored in their two losses.

The Rockets have regained home-court advantage, but it’s hard to call them favorites. Their backs were against the wall in games 2 and 4, and Golden State will have that same urgency for the first time in Game 5 on Thursday. Kerr will probably shrink his rotation in the same way that D’Antoni has, and his four All-Stars can share the offensive burden in a way that Harden and Paul cannot. There are a lot of small things on the margins that Golden State can still clean up, while the Rockets did almost everything right in Game 4 and won by only three points. They made the Warriors bleed. Finishing them off will be even harder.