Since he came to the NBA, Boston Celtics point guard Isaiah Thomas has always been the other Isaiah Thomas, having been named after (but not identically to) Detroit Pistons legend Isiah Thomas, as detailed in a recent ESPN video feature.
Yet now that the younger Thomas is on his way to his second consecutive All-Star Game, has established himself as the league's premier fourth-quarter scorer and is drawing "MVP" chants from Celtics fans, he's making a name for himself.
In fact, a case can be made that Isaiah is having a better season than Isiah -- and a lot of legends -- ever did. Can Isiah now be considered the other Isaiah?
Isaiah's rare combination of scoring efficiently and prolifically
After scoring a career-best 22.2 points per game last season, good for 11th in the NBA, Thomas has exploded in 2016-17. Only Oklahoma City Thunder point guard Russell Westbrook (30.9 ppg) is surpassing his 29.8 average.
Where Westbrook's lofty scoring average is largely a result of high volume, Thomas has not only maintained but improved upon the efficiency he showed in a smaller role. His .628 true shooting percentage would be the best of his career, and one of the best ever by such a high scorer.
If Thomas could get to 30 points per game, which he'll easily surpass if he maintains anything close to his 33.5 scoring average since New Year's Day, his true shooting would rank sixth in NBA history among 30-point scorers, according to Basketball-Reference.com. The three players who have done better? Hall of Famer Adrian Dantley and Golden State's Stephen Curry and Kevin Durant.
If anything, that list might understate what Thomas is accomplishing as a scorer. Remember, he's putting up these numbers in 34.5 minutes per game, a relatively modest figure for such a high scorer.
My favorite measure of scoring value is adjusted true shooting percentage, which adds or subtracts .050 to a player's true shooting for each percent their usage rate is above or below league average (20 percent) based on the typical tradeoff between usage and efficiency.
Since Thomas is using an estimated 34.5 percent of Boston's plays while on the court, his adjusted true shooting percentage is an even .700. That would make him the fifth member of the 700 Club dating back to the first season for which usage can be calculated, 1977-78 (when the NBA began tracking individual turnovers).
No precedent for Isaiah's efficiency among small guards
If there isn't much precedent for how well Thomas is scoring overall, there's none among players his size (5-foot-9). Even Curry, though small by NBA superstar standards, is 6-foot-3. Among players 6-foot-2 and shorter, a group that includes both Thomases and 2000-01 MVP Allen Iverson, high scoring and efficiency have almost never coexisted.
Of the 13 previous seasons where such players used at least 30 percent of their team's plays, just six saw them score with a true shooting percentage better than league average: three by Iverson (including his MVP campaign, when he was almost exactly average) and one apiece by World B. Free, Kyrie Irving and Tony Parker.
The most efficient of those seasons, by Irving in 2012-13, saw him post a true shooting percentage 3.5 percent higher than league average. This year, 5-foot-9 Isaiah Thomas has been an incredible 13.9 percent higher.
Because the Pistons' Thomas was more of a balanced point guard, his usage rate peaked at 27.0 percent during 1993-94, his final NBA season. In his prime, Thomas used about a quarter of Detroit's plays.
Yet because he was a poor 3-point shooter (29.0 percent career, the sixth-lowest mark in league history among players with at least 1,000 attempts per Basketball-Reference.com), Thomas experienced the same difficulty scoring efficiently as high-scoring small players have historically. His true shooting percentage was better than league average only once in his 13-year NBA career.
The case for the Pistons' Isiah: defense and playmaking
Even Isiah's most ardent supporters would surely concede that Isaiah has surpassed him as a scorer. The Hall of Famer's value was driven at least as much by his playmaking. Isiah averaged double-figure assists four times, including a league-high 13.9 in 1984-85. He averaged 16.6 assists per 100 team possessions that season, as compared to Isaiah's 9.2 assists per 100 possessions in 2016-17.
Meanwhile, though Isiah was a supporting figure in Detroit's outstanding Bad Boys defenses, he was never a liability at the defensive end of the court the way the shorter Isaiah has been with the Celtics. In his prime, Isiah consistently rated as about a league-average defender by box plus-minus, which is actually very good for a point guard. (Typically, point guards have the least value of any position on defense but the most on offense.)
For much of this season, Isaiah has famously been last in the league in the defensive component of ESPN's real plus-minus (RPM). He has replaced predecessors James Harden and Damian Lillard as the NBA internet's primary target of defensive shame, which is almost certainly unfair.
While RPM is the best of the all-in-one defensive metrics we have, in my opinion, it's also incredibly noisy from season to season, and Isaiah is a good example. In 2015-16, he rated 1.9 points worse than league average defensively by RPM, making him a below-average defender even by point guard standards but hardly the kind of outlier worth singling out as a problem.
This season's drop-off stems from Boston allowing 11.0 more points per 100 possessions with Isaiah on the court, according to NBA.com/Stats. As Andrew Johnson noted last week on Twitter, nearly half of that difference can be traced to Celtics opponents making 36.6 percent of their 3s when Isaiah is on the court and just 30.6 percent when he's on the bench. Neither mark is sustainable. Teams have little control over the 3-point percentages their opponents shoot over half-season samples, and an individual player surely has even less.
There's also no track record of Isaiah's size hurting Boston's 3-point defense. The Celtics allowed nearly the same percentage either way in 2015-16 and defended the 3 substantially better after dealing for him midway through the 2014-15 season.
Given his increased offensive workload, it seems reasonable that Isaiah has declined somewhat defensively, but RPM almost certainly overstates the magnitude of that difference.
The verdict: Isaiah has more work to catch Isiah
At the career level, it's indisputably true that Isaiah has a long ways to make Isiah the other Thomas. Isaiah is having a great season; Isiah had a great (if overrated) career.
As far as a season-to-season comparison, I think a similar conclusion is true. Isaiah's on pace to catch Isiah's best season (1984-85, when he was chosen for the All-NBA First Team for the second consecutive season on his way to three in a row) but still has a third of the season to go.
Besides the advantages I already elucidated, Isiah's more subtle edge is that he averaged 38.1 minutes per game in 1984-85, playing 81 games. As a result, Isaiah, who is playing fewer minutes and has already missed five games because of injury, will have to substantially outperform him on a per-minute basis. So far, I don't think that is quite the case.
If Isaiah plays Boston's remaining games, he's on pace for 18.4 wins above replacement player (WARP) by my metric. Isiah posted 18.5 WARP in 1984-85, which put him just ahead of Magic Johnson and behind Michael Jordan and MVP Larry Bird.
And that's without considering postseason play. Isiah's most memorable moments came in the Pistons' back-to-back championships, as well as their heartbreaking loss to the L.A. Lakers in the 1988 NBA Finals, which went the distance because of Thomas' Game 6 heroics on a sprained ankle. Isaiah has yet to star on the playoff stage, though his fourth-quarter performance this season suggests better results ahead.
If Isaiah can keep up his hyperefficient performance from the last month-plus through the rest of the regular season and through a deep playoff run, we can revisit the question. For now, Isiah Thomas remains the Isiah Thomas, even in terms of best single season.