And this recent stretch of terrific team play raises the question as to whether the Grizzlies need more Allen's defensive energy or Courtney Lee's offensive production.
Before the season, I entertained the discussion about whether Allen needs to start. At the time, the alternatives weren't compelling. Jerryd Bayless couldn't score reliably and Quincy Pondexter hadn't proven himself for more than a year. Neither were reliable defenders when on the floor.
Now that the Grizz have acquired a perimeter shooter who boosts the offense and is a decent defender, the calculus is different. Lee is making a difference as a scorer and holding his own defensively.
On the other hand, Allen, who has missed 12 games due to a left-hand ligament injury and is listed as day to day, per The Commercial Appeal (subscription required), doesn't score enough to complement his singular defensive abilities.
Memphis' attack is too tenuous to cut Lee's minutes
The Grizzlies' recent surge—they've won nine of 11 since trading for their new guard—is due in part to Lee's scoring. Six of the eight games in which he's scored in double figures for the Grizz were victories. And he's played well in tightly contested games: The three games in which he scored 19 or more were decided by three or fewer points. On Jan. 14, he sealed a victory against the Oklahoma City Thunder by hitting a pair of free throws.
Since joining Memphis this season, Lee's averaging 14 points in 30.1 minutes per game. He's shooting a remarkable 55.3 percent from the field, 41.9 percent from beyond the arc and 96.4 percent from the line.
While this is unsustainable, he won't fall hard, since he's hit 48.2 percent from the field since the beginning of last season.
He expands the Grizz offense in ways that other Memphis players are incapable of doing. His three-point shooting is among the best on the team, and he's terrific at spacing the floor.
Mike Conley spoke glowingly about Lee's floor-spacing ability, telling NBA.com, "It's key that he's able to stretch the court for us. With me, him, Mike Miller out there, it gives Zach [Randolph] and Marc [Gasol] more space. Having a lot of guys that could space the court, we didn't have that before."
Allen's defense isn't needed as much as it seems
The 32-year-old is solid defensively, despite not performing as well as in prior years. He's allowing 102 points per 100 possessions, which is third best on the team. If he were qualified at this point, he'd be second in the league in steals rate (3.9 percent).
But the team's recent defensive awakening has come with the return of Marc Gasol. NBA.com shows that in the last eight games, the Grizz are allowing almost 10 points per 100 possessions fewer than their season rate. They've held opponents to 90 or fewer points in seven of those games.
Hence, the Grizz are improving greatly without their perimeter stopper. Any further improvement after Allen's return will be incremental, helping Memphis move up a few spots in key defensive categories.
Lee's defense is a mixed bag. He's allowing 108 points per 100 possessions. According to NBA.com, he's been up and down defensively since joining Memphis, but his defensive rating differential is among the best for Grizz rotation players.
Having reasonable defense to go with strong scoring means Lee provides a greater overall impact for the Grizzlies than does Allen. The latter puts up only 10.2 points on 8.5 field-goal attempts per game, along with a 16 percent turnover rate, which doesn't do enough to supplement the defense that he showed before the injury.
Conclusion: Allen may lose standing, but shouldn't fall from the lineup
Lee may merit more minutes due to his overall output, but that doesn't mean Allen can't start. The veteran could start at the 3 spot instead of Tayshaun Prince.
Indeed, starting Allen ahead of Prince means losing a considerable amount of length, since Prince is two inches taller and several inches longer. Even though Allen doesn't measure well next to small forwards, he defends better than Prince.
Prince is forgettable on both ends of the floor. He's second worst among active Grizz players with 94 points produced per 100 possessions. His defensive rating is down to 108, but that's due to the fact that, according to NBA.com, he defends best when paired with Lee.
Neither Allen nor Prince shoots much, but Allen's field-goal clip is 9.4 percent better, and he averages four more points per game.
The Grizz have plenty of backcourt players, among whom Allen ranks highly. Even in an off year, he's one of the team's best defenders. Combining that with accurate shooting makes him a valuable No. 3 backcourt player behind Lee and Mike Conley.
Statistics are current through Jan. 30 games. Unless otherwise noted, advanced metrics come from basketball-reference.com.