NBA Position Battles: Should Patty Mills Start for the San Antonio Spurs Instead of Tony Parker?

Parker has been a fixture in the Spurs starting lineup for a decade and a half. Is it finally time for a change?

Tony Parker being the starting point guard of the San Antonio Spurs is one of the few reliable things left in the NBA. Of the 1,097 games he's played in his career to date -- all with San Antonio -- he's started 1,084 of them spanning 16 NBA seasons (with an additional 205 starts in 213 postseason games played).

He's still starting and contributing to the Spurs' 20-5 record at almost 35 years of age, and it would probably be blasphemous to suggest that anyone run the point for them other than the fiery francophile until he retires.

Well, sorry to be so profane, but Patty Mills is playing far better basketball than Parker right now and probably deserves a shot at starting.

From a raw numbers perspective, they look like they are practically the same player:

Tony Parker 25.3 9.9 1.8 4.7 0.4 0.1 1.6
Patty Mills 23.4 11.5 2.0 3.6 0.8 0.0 1.3

But when you looking at scoring efficiency, Mills is better by a mile:

Player FGM / FGA FG% 3PM / 3PA 3P% FTM / FTA FT% eFG% TS%
Tony Parker 4.0 / 8.9 45.0% 0.4 / 1.0 35.3% 1.5 / 1.8 86.7% 47.0% 51.2%
Patty Mills 4.1 / 8.4 48.8% 2.1 / 4.8 43.7% 1.3 / 1.4 94.1% 61.2% 64.3%

The differences in field goal percentage (3.8%), three-point percentage (8.4%), and free throw percentage (7.4%) don't look particularly jarring at first glance. However, the differences of 14.2% in effective field goal percentage (weighted twos and threes) and 13.1% in true shooting percentage (weighted twos, threes, and freebies) show how significant the gap between the two really is.

As a result, just about all of the one-number advanced metrics skew in Mills' favor by a fairly noteworthy margin:

Category Tony Parker Patty Mills
nERD -0.6 2.1
Offensive rating 104 122
Defensive rating 110 108
Player efficiency rating 12.4 18.9
Win shares 0.6 2.2
Win shares per 48 minutes .069 .180
Box plus/minus -4.1 3.0
Value over replacement player -0.2 0.7

If you didn't know "Player A" in this scenario was Tony Parker -- a six-time NBA All-Star, four-time champion, and shoo-in Hall-of-Famer -- there's almost no way you'd start him over "Player B", Patty Mills.

Starting with our proprietary metric, nERD -- a player ranking that measures the total contribution of a player throughout the course of a season, based on his efficiency -- it's clear Mills is contributing more wins to the Spurs than Parker is this year. Comparable to win shares, nERD gives an estimate of how many games above or below .500 a league-average team would win with the player in question as one of its starters.

Of the 15 players that have played for the Spurs so far this season, Mills is second on the team in nERD at 2.1 (behind Kawhi Leonard's 5.7), while Parker is in a three-way tie for 15th (or dead last) at -0.6 with Manu Ginobili and rookie Dejounte Murray.

In other words, the Spurs would have won roughly 2.7 more games to this point in the season (closer to 23-2 instead of 20-5), had Mills started instead of Parker. That's admittedly an imprecise way to use the statistic, but you get the point.

There's perhaps no better stat to show the chasm that exists between how much better the Spurs have been with Mills than Parker than their on/off splits:

On/Off Splits Off Rtg Def Rtg Net Rtg
Tony Parker on 107.2 105.9 1.3
Tony Parker off 108.8 99.6 9.3
Patty Mills on 113.5 98.1 15.4
Patty Mills off 103.1 105.4 -2.3

The whopping 17.7 difference in net rating (points scored minus points allowed per 100 possessions) between when Patty Mills is on the court compared to when he's on the bench is the largest on the Spurs.

And if you're wondering about fit with the starting unit, San Antonio's regular starters (Parker, Danny Green, Leonard, LaMarcus Aldridge, and Pau Gasol) have a respectable net rating of 6.8 in 167 minutes played (108.3 offensive rating, 101.5 defensive rating), but the team's next most-used lineup with Mills in place of Parker and Kyle Anderson in place of Green (which was used for five games during which Parker and Green were both unavailable due to injury) has a fantastic net rating of 19.7 (112.9 offensive rating, 93.2 defensive rating) in 50 minutes played.

So, can we reason that Patty Mills has earned the right to start and play more minutes than Tony Parker? Almost certainly, yes. Do we know better than Gregg Popovich -- one of the best coaches in NBA history -- who is deciding to stick with Parker? Almost certainly not.

But the numbers suggest Pop might just be wrong on this one. Not that anyone would ever want to tell him that.