This is the Jaylen Brown vs. Donovan Mitchell series

Jaylen Brown and Donovan Mitchell have crossed paths before. They were teammates on that 2019 FIBA World Cup Team USA with then current, former, and future Celtics Jayson Tatum, Kemba Walker, Marcus Smart, and Derrick White, but their bromance didn’t really start until the Orlando bubble. Who could forget this meet cute content (language NSFW)?

Since then, they’ve become active members of the NBPA executive board together, most recently hooking up at Sanctuary last summer and appearing on Point Forward, a podcast hosted by Andre Iguodala and Evan Turner. Mitchell also participated in one of Brown’s slam dunks on All-Star Saturday.

Unfortunately, the two friends are now frenemies because it’s all fun and games until, well, they’re postseason games.

“Ain’t no friends in the playoffs,” Brown said after Monday’s practice, preparing to face Mitchell and the Cavaliers in Round 2.

The feelings are mutual for Mitchell. “Two of my friends, but to be honest, I stopped talking to them when we saw how the [bracket] was going to figure out,” he said of potentially facing Brown and Jayson Tatum. “It’s all competition. I expect nothing but the best from them and vice versa.”

There are going to be hundreds of decisions and adjustments made throughout the series that won’t involve Mitchell or Brown. Will the Celtics use the three-point differential in their favor? Can Max Strus and Caris LeVert become TD Garden villains again as Cavaliers? Does the series pivot on the success of Evan Mobley? But in crunch time, games and ultimately the series could come down to Cleveland’s most explosive offensive player going up against Boston’s best chance to stop him.

For most of the regular season and particularly in the later half, Brown has embraced the role of defensive stopper and taken on the more challenging one-on-one assignments. In five minutes defending Luka Doncic last March, the MVP candidate only got up four shots and made two. In nearly eighteen minutes checking Anthony Edwards in the regular season, Edwards shot just 6-of-13 with two turnovers.

But Mitchell is a different animal. He was a force against Orlando, scoring 89 points in Games 6 and 7 and shooting a whopping 33 free throws over the last three games of that series. He’s on a gimpy knee that robbed him of thirteen games in March, but even Mitchell at 80-90% is dangerous. He’s not a crafty foul merchant like Jalen Brunson. Instead, Mitchell is a hit-the-hole-hard type running back with the versatility of an option QB.

In Brown’s own words, “Donovan is a explosive, strong, three-level scorer. I think his strength gives him an advantage on a lot of defenders. He’s good at changing direction — he’s a good basketball player.”

Derrick White and Jrue Holiday will surely get their licks on Mitchell, too. They’re two of the best on-ball, point-of-attack defenders in the league, but he torched them in the regular season (13-of-18 in 74 possessions). Through 45+ possessions, Brown held him in check (3-of-6. This is Brown’s series to make a marked difference. Put simply, what Mitchell (6’3, 215 pounds) is in offense, Brown (6’6, 223 pounds) is on defense: a big body that can bang with the speed and agility of a big cat on the hunt.

A series isn’t decided by two players. There are at least eight hundred possessions between now and the end of the conference semis. However, a bulk of them, many in the fourth quarter and in the clutch, will hinge on what comes between friends.