Markieff Morris is a fine defender. He’s got good instincts, size and athleticism, and he was a positive on that end all season.

But he’s not Kawhi Leonard-type good. He’s not switch-onto-one-of-the-best-scorers-in-the-NBA-in-space-type good. And on a bum ankle — no, that’s not Marcus — he had no chance at stopping someone as good as Isaiah Thomas.

Yet in the first two games of the Washington Wizards’ second-round series against the Boston Celtics, Morris has found himself staring down the 5-9 All-Star point guard. Even the simplest of high ball screens — even plays where no screen was set at all and Jae Crowder or Al Horford simply crossed paths with John Wall at the top — left Morris on an island against Thomas, one of the most creative and quickest leading scorers in the NBA. The results were … well, see for yourself:

That particular pivotal play came as a result of a stagger-screen action at the top of the key. Crowder is at the top, and Horford is stacked below him. Thomas’ goal is to get the switch, and he has two screeners (with two big men defending them) from which to choose.

The switch-on-any-screen mentality is becoming more and more common in the NBA. It was a core philosophy for the Warriors in their 2015 run as the best defense in the NBA, and finding big men who can handle guards on the perimeter has become a bigger priority than low-post scoring by a long shot among the more modern-thinking NBA teams. The 2017 NBA playoffs are littered with highlights of guards dribbling circles around big men, and that’s the result of these switches.

But those sequences haven’t defined any other series quite like Wizards-Hawks. This screen capture from that video above shows exactly how easily he gets Morris to switch to him thanks to Crowder’s presence — it’s barely even a screen.

But that’s not the frustrating one for Wizards fans. It’s this one:

Note how Wall wanders over to cover Crowder with little urgency. Meanwhile, Thomas lets Horford fight down toward the basket against Marcin Gortat, knowing that he doesn’t need any extra help. He has the matchup he wants for an isolation basket at a key moment in a close game.

There’s not an ideal solution to get Wall back on Morris here, at that point. There are two basic ways to defend a pick-and-roll, though: switching and hedging. The hedge, the other option in this case, would mean that Morris would have stepped out in front of Thomas only for long enough to prevent the drive and allow Wall to slide back in front of him.

Teams don’t like doing that because it potentially leaves the screener (in this case, the very capable Crowder) able to sprint out and get an open catch-and-shoot 3. But the downside is pretty enormous, too: Isaiah Thomas matched up on Markieff Morris with a ton of space to operate.

We saw James Harden destroy Thunder center Enes Kanter, notoriously one of the NBA’s worst defenders, in these exact situations a couple times in Round 1.

https://www.youtube.com/watch?v=BpBB9HxC8-M

The switch sometimes is simply inevitable, though. Crowder easily could have cut hard in the Celtics-Wizards example, and Wall can’t simply leave him alone. But watch what Clippers guard J.J. Redick does in helping center DeAndre Jordan after a switch vs. the Jazz’s Gordon Hayward.

Redick cuts off the passing lane to Jazz screen-man Rudy Gobert while pursuing Hayward the entire way. He successfully forces Hayward into a tougher shot, which of course the Jazz All-Star cans.

Wall and the Wizards have a similar option granted because of Thomas’ unique size. Wall has 7 inches of height and 9 inches of wingspan on Thomas, plus an athleticism advantage. He could have pursued Thomas while keeping track of the passing lanes and bought Morris enough time to rotate back after the hedge. It’s complicated by Horford being involved in the play, but that only gives the Wizards another, more palatable switching option, if Gortat is forced to rotate onto Crowder.

The pace of the play is a key factor, too. And it’s a recurring one. The Celtics didn’t always use a stagger screen to elicit the switch. Morris ended up on Thomas on several occasions thanks to much simpler early-shot-clock moves. The constant, though, was that Thomas wanted to use the matchup in an isolated context rather than as part of a play. He scored 53 points not by looking for zip-line passes off screens but by playing matchups to his advantage.

High ball screens have become a standard for offenses to start possessions. Switching prevents an easy quick shot, which can be deadly. They’re incredibly effective when the personnel is right, as with the Warriors’ Draymond Green.

They’re also a bit of a crutch or a force of habit. Having the ability to switch on attacking plays is a tremendous asset. Switching out of habit whenever an opponent runs a lazy screen as soon as the ball crosses halfcourt is simply a way to set yourself up for mismatches. There’s no reason to hand the advantage of a slower defender to every opposing point guard on every possession; Morris’ ego shouldn’t be bruised by Wall calling off the switching and wanting to guard Thomas on key possessions.

Playoff basketball differs from regular-season basketball. The pace slows, and physicality increases. Players are allowed, if not encouraged, to get grabby around screens, and passing options should be limited if all defenders are locked in with high effort, as they should be.

That’s why isolation basketball comes up so often in the playoffs. Always has, always will. The Wizards need to realize that Thomas wants these matchups and find a way around the switch. Maybe Wall picks Thomas up later, or maybe he handles Crowder more aggressively.

But if Markieff Morris spends the rest of this series handling Isaiah Thomas alone on key possessions, there will only be two more games. Game 3 is Thursday night (8 p.m. ET). Let’s see how quickly Scott Brooks’ coaching staff can adjust.