The Boston Celtics record after eight games is 6-2, but their record in fourth quarters is the opposite, 2-6. The only fourth quarters they’ve won have been in their 35-point win over Chicago, and their 11-point road win over Orlando. 

It raises the question: Do the Celtics have a burgeoning fourth-quarter issue?

Before we dive into things, let’s get the very big caveat out of the way. Eight-game sample sizes are minuscule, and they don’t determine anything. The Celtics can rout Charlotte and Milwaukee Friday and Sunday and change everything in this piece. 

Still, losing leads is nothing new for the Celtics. The discussion around their late-game execution is more on-again, off-again than a high school relationship. They are absolutely not alone in the NBA, and everyone knows no lead is safe, but that doesn't change the desire to avoid that as much as possible. The Celtics would like to win more than one of every three fourth quarters.

Big leads, shrinking margins

To get to the fourth we have to start in the first, where the Celtics are generally building big leads. They're a cumulative +41 in first quarters and +69 in first halves. Everyone in the lineup plays in the first half, so it’s hard to pin this on any particular person. 

Things change for them in the second half, though. They're only +8 in third quarters, and they drop to -30 in fourth quarters. 

Right away, it feels like a classic case of a team relaxing when they get up big. They’ve held leads of 20 points or more in four games so far this season, and only once did it stay there (their 134-99 win over Chicago). They beat Chicago the second time by 14 after leading by 32. The Celtics had 22-point leads over Detroit and Milwaukee and ultimately fell behind in both games. They lost to the Pistons on opening night, but they recovered Wednesday night to beat the Bucks. 

Where the runs happen

The worst of the lost lead in Detroit came after the 7:34 timeout of the fourth, when a lineup of Jayson Tatum, Derrick White, Paul George, Mitchell Robinson, and Baylor Scheierman gave up a 12-0 run before Joe Mazzulla called another timeout.

Against the Knicks, the Celtics saw a 10-point lead cut to one between the 6:53 timeout of the fourth quarter and the 1:41 mark, starting with a lineup of Tatum, White, Robinson, Payton Pritchard, and Jordan Walsh. 

They were up seven with 7:49 to play against Brooklyn when the Nets went on a 9-0 run. Three of those came just before the 7:39 timeout, and Boston came out of that with George, White, Sam Hauser, Walsh, and Robinson.

Milwaukee’s run was steadier throughout the fourth quarter. The Celtics had George, Scheierman, Luka Garza, Robinson and White/Hauser on the floor. Neemias Queta and Walsh checked in at 7:21 (Scheierman later came back in for Walsh at 4:22) as Boston closed the quarter out 18-11. 

The Celtics never led against Houston, so I’m not really concerned with that. Also, I’m not going to factor in any lost garbage time minutes in their 35-point win over Chicago. 

The most curious thing so far is that the runs seem to get bad around the first timeout of the fourth quarter, somewhere between 9:00 and 4:00. Runs have certainly started sooner, but that's about when teams really seem to pounce. 

The Mitchell Robinson question

Robinson also seems to be a constant in these lineups, which does raise the question of whether he’s running out of gas in those moments. Mostly, it seems like Boston is struggling to score and hold off opponent runs, which leaves them cross-matched in transition and susceptible to open three-pointers, which have crushed them in fourth quarters. The Celtics are currently allowing the fourth-highest fourth-quarter three-point percentage (38.5%). Part of Robinson’s job is to set screens, get guys open, and crash for putbacks so they can score and mitigate these runs.

Robinson has two fourth-quarter offensive rebounds, total, in six games. For context, Baylor Scheierman has five and Luka Garza has three. Robinson’s offensive rebound rate is currently 11.1% overall, just behind Garza’s 12.8%, but in the fourth quarter, Robinson is only getting to 4.9%. Garza is at 10% in fourth quarters and Scheierman is at 9.1%.  

Robinson is also a cumulative -32 in fourth quarters and -28 in close games. But to be fair, Tatum is -19 in fourth quarters and -14 in close games, White is -16/-15, Hauser is -17/-14, Walsh is -17/-19, and Pritchard is -14/-3. 

He’s not solely to blame. The Celtics are also fouling a lot, putting opponents on the line 8.1 times per fourth quarter, which is ninth-worst in the league, and that's a team-wide issue. 

But it’s hard not to look at the Robinson minutes right now and think they're a big part of the problem. Queta has played more than 40 fourth-quarter minutes compared with Robinson’s 28, but Queta is +6. Garza is -4 in fourth quarters in similar minutes as Robinson. 

Robinson is taking a lot of heat, and something like this won’t help. Mazzulla, for one, isn’t thrilled with Robinson taking the slings and arrows right now. 

“The greatest thing that you can give a guy like Mitch, who's been in the league for nine years and played on a championship team, and decided to come to our team, is to empower them and to ask more of them, and that just takes a little bit of time,” he said after the Bucks game. “He's one of the best rebounders of all time. So any chance there is a little bit of a dip, we all have to hit the panic button, and it's just not the case. His process has been great, and it'll continue to be better and better for us.”

Fourth-quarter issues don’t fall on one player, but there's also no doubt that Robinson playing better in those patches of the fourth will help the Celtics. Boston needs stops and baskets in those moments, and they either need Robinson to provide them, or they need to adjust the lineups. 

It’s too early to say which way they should go. Right now, all these numbers do is highlight a trend. We’re the guards at Swamp Castle watching Sir Lancelot run towards us from a distance. What we don’t want is for him to pounce on us and go on a rampage. 

The Celtics have had some rough fourth quarters so far, but they’ve survived most of them, which is the good news. The trends are starting to show themselves, so now we know what to watch for and when, and from there we can see how the Celtics decide to adjust.