Inside the numbers: Boston bench outplaying the starters

Midway through the third quarter of Monday's game it looked like the Los Angeles Clippers would cruise to their eighth win in 11 games. With little resistance from the Boston starters, the Clips led 71-48 with 4:13 remaining and had the Staples Center patrons more concerned with their postgame plans than the game's final quarter.

But Boston, propelled by reserves Brandon Bass (17 points), Marcus Smart (14 points, seven assists) and Marcus Thornton (15 points), didn't go quietly. The Celtics cut the lead to 91-88 on a Thornton 3-pointer with just under four minutes remaining, but couldn't quite close the deal and eventually fell 102-93.

The starters combined for just 34 points on 28.9 percent shooting and each posted a plus/minus of minus-13 or worse. Meanwhile, the bench contributed 59 points and dished out 15 of the team's 24 assists. It's critical to make note of the opponent here, as Los Angeles has one of the league's best starting fives and, even with Jamal Crawford, one of its worst reserve units. Boston's starters were tasked with stopping Chris Paul and Blake Griffin while the bench contended with the likes of Glen Davis and Austin Rivers.

But the starters' struggles didn't begin with Monday's loss - in fact, Boston's top unit has been struggling for about a month now. In the eight games since Jeff Green was traded to the Memphis Grizzlies, the Celtics' new opening lineup is scoring 87.1 points per 100 possessions, which Mass Live's Jay King noted is worse than Philadelphia's league-worst 91.0 from last season.

In fairness, Boston's starting lineup has undergone massive changes recently. Jae Crowder has mostly replaced Green since the deal and Evan Turner has taken over Rajon Rondo's spot after the latter was dealt to Dallas last month. Those are two downgrades, and some slippage is to be expected.

But since Rondo was traded on Dec. 18 the Celtics' opening five has been among the worst in the league. During the 16 game stretch (in which the team has gone 4-12), they've combined to shoot 43.8 percent from the floor and 31.1 percent from deep, both bottom six among NBA starting lineups. Here's the shot chart since the Rondo move:

The Celtics have been about league average defensively, and Crowder and Avery Bradley are both plus perimeter defenders. But that lack of scoring submarines the defensive efforts.

It's scary to think where Boston would be if the bench hadn't stepped up during this stretch. The bench is third in minutes played since and only six benches average more points than the Celtics' 41.6. With Smart growing more comfortable as his rookie campaign progresses, the bench is assisting on 64.9 percent of its baskets and sports a tidy 2.2 assist/turnover ratio since the Rondo trade.

Here are Boston's ratings since Dec. 18:

Offensive rating

Starters: 96.5 (27th in the league among starting units)

Bench: 103.7 (eighth in the league among bench units)

Defensive rating

Starters: 104.6 (10th)

Bench: 105.7 (10th)

Net rating

Starters: -8.1

Bench: -2.0

There isn't really a quick fix available here. Pairing Bass and Jared Sullinger would help offensively, but it would rob the unit of some serious size. Smart is still coming into his own and Turner has distributed the ball well despite his recent shooting slump. There are different ways for Brad Stevens to tinker here and there, but it's become evident that the Celtics are going to struggle against more talented starting units almost every night, while their deep bench of solid contributors will look better against fellow reserve squads.

Again, it's a small sample size and the Celtics are finding their way after dealing their two highest-usage players in the last 30 days. But the early returns aren't promising, and Boston needs to get off to better starts if it hopes to see improvement soon.

Photo credit: Andrew D. Bernstein