The NBA playoffs are ruthlessly Darwinian, and the margin for error gets a lot thinner in the second round. For the most part, the teams that were expected to advance did — the snakebitten Clippers were the only top-four seed in either conference to get knocked out. There are no bad teams left: The eight remaining teams won an average of 55 games this season. Going up against the best players and coaches in the league will expose even the smallest weakness.

The first few games of a series are a feeling-out process, with each team probing the other for places to attack. As the series progresses, the clubs morph into the versions of themselves most capable of matching up with the other.

A team can change dramatically between the start of a series and the end of one. Look at the Celtics and Raptors in the first round: Brad Stevens and Dwane Casey each took one of their big men out of the starting lineup, going smaller and faster to regain the edge.

Making adjustments is the name of the game in the postseason. Coaches can hurt their teams by stubbornly sticking to what worked in the regular season, but more often than not, the bigger problem is a lack of good options on their bench. As Donald Rumsfeld once said, “You go to war with the army you have, and not the army you might want.” Coaches have to make do in the playoffs.

With that in mind, here’s a look at five possible adjustments that could change how the second round plays out:

The Raptors Starting P.J. Tucker

In Toronto’s loss to Cleveland in last year’s Eastern Conference finals, LeBron James averaged 26 points, 8.5 rebounds, and 6.7 assists a game on 62.2 percent shooting. LeBron is going to score, but even he isn’t usually that efficient. He shot 49.5 percent from the field in Cleveland’s other three series. DeMarre Carroll got the initial assignment, and he wasn’t even a speed bump for LeBron on his way to the rim. Nor did Carroll perform much better against Giannis Antetokounmpo in the first round: The Bucks star averaged 24.8 points, 9.5 rebounds, and four assists per game on 53.6 percent shooting against the Raptors.

Raptors GM Masai Ujiri added P.J. Tucker at the deadline to give his team a tough-minded and physical defender who could body up LeBron. Toronto had a defensive rating of 109.5 when Carroll was on the floor in the first round; it dropped all the way to 95.3 with Tucker in. While those numbers are skewed in part because of how many minutes Carroll played in two-big-man lineups (with Jonas Valanciunas and Serge Ibaka) that couldn’t keep up with Milwaukee, they fit the pattern of Carroll being unable to hang with the best players at his position.

Making the switch wouldn’t be easy for Casey. Carroll is in the second year of a four-year, $58 million contract, while Tucker will be an unrestricted free agent in the offseason. Nevertheless, the Raptors need Tucker, their best perimeter defender, on LeBron for as many minutes as possible in this series to have any hope of an upset. LeBron is still at the peak of his powers, and Tyronn Lue will put him in über-small lineups that give him plenty of space to attack the rim. Toronto can’t afford to let him score as easily as he did last year.

The Wizards Featuring Otto Porter Jr. More

The biggest piece of news from Washington’s Game 1 loss to Boston on Sunday was Markieff Morris severely rolling his ankle, since the Wizards don’t have the depth to withstand injuries to any of their key players. Without Morris, the Celtics were able to hide Isaiah Thomas defensively by putting him on Kelly Oubre Jr. when the starters were in. If Morris returns, Thomas will spend a lot of that time on Porter, and that’s a matchup the former no. 3 overall pick has to exploit for the Wizards to take the series.

Porter had an efficient game on Sunday, with 16 points on 7-of-10 shooting and 11 rebounds, but most of his damage came from playing off the ball. The Wizards didn’t run much offense through him, even when Thomas was guarding him. At 6-foot-8 and 198 pounds with a 7-foot-1 wingspan, Porter has more than a foot on the Celtics star, and he can get clean looks pretty easily. Thomas lost his tooth trying to guard Porter on this play, and the physical punishment should only get worse as the series goes on:

Porter has been one of the most improved players in the league this season, averaging 13.4 points, 6.4 rebounds, and 1.5 assists a game on 51.6 percent shooting. The Wizards will need every bit of offense they can get in order to beat the Celtics in what should be a thrilling, back-and-forth series, and the fourth-year forward could tap some more potential if he’s given a bigger role. He can do a little bit of everything against such an undersized defender, whether it’s posting Thomas up, forcing Thomas to chase him around screens (and making Thomas take a few hits in the process), or putting him in the pick-and-roll. Porter, who is playing for a contract this offseason, could make himself a lot of money in the next two weeks.

Related 13 Lessons Learned in Round 1 of the NBA Playoffs

The Rockets Attacking Tony Parker

Parker had a bit of a renaissance in the Spurs’ first-round victory over the Grizzlies, averaging 16.3 points per game on 53.3 percent shooting after getting only 10.1 points on 46.6 percent shooting in the regular season. With LaMarcus Aldridge struggling against Memphis’s physical front line and Manu Ginobili scoring only 14 points all series, San Antonio desperately needed Parker’s ability to create off the dribble to complement Kawhi Leonard. But while Gregg Popovich was able to hide the 34-year-old on defense against the relatively punchless Grizzlies, it will be harder against the Rockets, who have one of the most potent offenses in NBA history.

Houston needed Patrick Beverley to defend Russell Westbrook in the first round, but Lou Williams and Eric Gordon could have bigger roles against San Antonio. Williams and Gordon are two of the most lethal bench scorers in the league, and there’s no way Parker should be able to defend either at this stage of his career. According to the tracking numbers at Synergy Sports, he was only in the 17th percentile of defenders in the pick-and-roll this season. The Rockets need to get him in space and attack him early and often.

As potent a scorer as James Harden has been in Houston, his efficiency dips in the postseason. In 39 games over five playoff runs with the Rockets, he is shooting only 41.3 percent from the floor. There’s only so far a one-man offense can go against the best teams, as Westbrook found out in the first round. Williams and Gordon give the Rockets an extra dimension on the perimeter they haven’t had the last few years, and playing them next to Harden could force the Spurs into some tough defensive decisions.

The Spurs Using Kawhi Leonard on the Rockets’ Big Men

The headline matchup in this series is Harden vs. Leonard, with the two-time Defensive Player of the Year guarding the likely runner-up for this season’s MVP award. However, Harden gets most of his points in the pick-and-roll in Mike D’Antoni’s offense, so putting your best defender on him at the start of the possession can be pointless when he’s going to be involved in so many screens. The more defenders Harden attracts in those plays, the easier it is for him to create open looks for the shooters Houston has around him.

One trick Popovich could try is putting Kawhi on either Ryan Anderson or Clint Capela and then switching the screen while keeping the other Spurs defenders at home. Kawhi is such a long and physical defender that neither Anderson nor Capela should have much success posting him up, and even the threat of the switch could prevent the Rockets from using them to screen for Harden, which is the only way they are going to hurt the Spurs. It would also give Kawhi some possessions off defensively, which is important considering how much he does on offense.

Popovich has been hesitant to play Kawhi much as a small-ball power forward, but he could still keep two traditional big men on the floor by putting one of them on Trevor Ariza, who can’t create his own shot. If the Rockets use Ariza as the screener to force the Spurs bigs to guard in space, San Antonio could trap Harden and force Ariza to make quick decisions on the move as the roll man. Because Ariza is Houston’s only wing defender with the size to match up with Kawhi on defense, they can’t afford to take him off the floor much in this series. Popovich isn’t likely to try something this unorthodox early in the series, but it’s something he could have in his back pocket if his team can’t slow down the Rockets offense.

The Jazz Tightening Up Their Rotation

Going from a Clippers team without Blake Griffin in the first round to the Warriors in the second is like going from playing on Rookie mode to All-Madden. Utah has to play near-perfect basketball to challenge a healthy Golden State team. The Warriors put pressure on their opponent for the entire 48 minutes: Even when Kevin Durant and Steph Curry are out, they still stagger the minutes of their starters so that Draymond Green and Klay Thompson are in. The Warriors are like sharks who can detect a drop of blood in the water from a mile away: Put a player who can’t defend on the floor for any amount of time and they will attack.

Quin Snyder was forced to dig deeper into his bench against the Clippers because of Rudy Gobert’s injury, and he won’t be able to get away with that against the Warriors. Boris Diaw was effective in the first round, especially once Blake Griffin went out, but it’s hard to see how he can stay in front of the Warriors guards when they force him to defend in the pick-and-roll. Shelvin Mack takes a lot of questionable shots, and the less said about Raul Neto’s playoff performance so far the better.

The Jazz should try a seven-man rotation with Gobert and Derrick Favors at center, and five perimeter players (George Hill, Gordon Hayward, Joe Ingles, Joe Johnson, and Rodney Hood) splitting the other four spots in the lineup. All those guys can defend multiple positions, spread the floor, attack close-outs, and make plays on the move. If Snyder has to buy a few extra minutes, Dante Exum is worth a shot, since he has the physical tools to at least hang defensively. The deeper a team advances in the playoffs, the fewer players it can trust, and playing the Warriors means treating every game like the NBA Finals.