Players improve in their second year with a team, especially if that team is the Spurs, who have intricate defensive rotations and demand full effort.
At least, that's the perception fans around the league have. For the Spurs, fans can point to Stephen Jackson increasing his minutes by 18 and points by 8. There is Manu Ginobili and Tony Parker making big jumps from their rookie year to year two. Even smaller improvements can be seen, such as Fabricio Oberto increasing his minutes by 9, points by 2.7 and rebounds by 2.6.
The supposed reason for these improvements is that a player has had a year to understand the offensive sets, learned how to play with his teammmates and grasped any defensive nuances. Logically it all makes sense, especially with the Spurs. Popovich is notorious for his reluctance to play new players because he is stubborn with his rotations, just ask Michael Finley, making it hard for first year players to become fully integrated.
However, I have often wondered if this improvement is statistically true. Our minds tend to remember the good, which is why we think of Jackson's improvement or Bruce Bowen's big jump in three point field goal percentage, but we easily forget the players who regressed, such as Francisco Elson or Rasho Nesterovic.
To have a better idea about the difference between a player's first year with the Spurs and his second year, I turned to one of my favorite basketball websites - basketball-reference.com. I found all the players since 1998-1999 who joined the Spurs and played at least two seasons with significant minutes per game (greater than 10) and made a spreadsheet with their statistics. I included some basic stats, such as points, rebounds and assists, but I really wanted to look at their advanced statistics because so much can change from year to year, such as playing time or usage, and I wanted to utilize statistics that would minimize those changes. This spreadsheet allowed me to see the differences from year one to year two, which I then averaged for the 25 players who fit the criteria.
The following chart shows the average difference from year one to year two. I've used some of these advanced statistics in the past, but here is a key for those who aren't familiar with them.
TS% - True Shooting %, takes into account 2's, 3's and free throws
eFG% - Effective FG%, takes into account that 3's are worth more than 2's
TRB% - Total Rebound %, estimate of total available rebounds a player grabs while on the court
AST% - Assist%, estimate of teammates FG a player assisted while on the court
TOV% - Turnover %, estimate of turnovers per 100 possessions
ORtg - Offensive Rating, estimate of points produced per 100 possessions
DRtg - Defensive Rating, estimate of points allowed per 100 possessions
OWS - Offensive Win Shares, estimate of # of wins a player contributed to because of his offense
DWS - Defensive Win Shares, estimate of # of wins a player contributed to because of his defense
WS - Win Shares, estimate of # of wins contributed to
I'll readily admit that these numbers are not perfect. Twenty five players is too small of a sample size to build a great dataset. Also, merely averaging them is not that most advanced way to look for improvement. I did not determine if the change was statistically significant, but it is a good jumping off point for discussion.
So what do these numbers tell us?
First, the average playing time was almost the same from year one to year two. While players like Jackson and Ginobili had significant increases in minutes, others like Steve Kerr, Steve Smith and Brent Barry saw significant decreases. Also, the basic statistics (points, rebounds, assists) showed slight improvements but not big enough improvements to blow me away.
I was intrigued to see that the average PER increased by 0.39. While it is not a large improvement, I found that players improved their PER more often than not, with 15 showing some improvement. This tells me that players were slightly more efficient in their second year with the team. Standouts in this area were Jackson (6.6 improvement), Parker (4.8), Ginobili (3.8), Oberto (2.6) and Kurt Thomas (2.9). The biggest drops were Nesterovic (-3.3) and Matt Bonner (-4.1).
I wanted to see if the TS% or eFG% improved at all because players were more comfortable with the offense and found better shots. It seemed that there was not a change. Some players improved (Bowen, Oberto, Jackson) but just as many regressed (Elson, Smith, Mario Elie).
To me, the most telling numbers were the AST% and TOV%. These showed that players assisted on more field goals while on the court and had fewer turnovers. Now, these numbers might be slightly skewed because they include Parker and Ginobili, but I was still impressed. This tells me that players felt more comfortable with the Spurs in their second year and protected the ball better, which has always been a key to the Spurs offense.
The ORtg showed that players, on average, contributed two more points per 100 possessions in their second year. Once again, this indicates that they are more comfortable with the offense. Of course, Jackson and Parker showed big improvements, but so did Nazr Mohammad and Kurt Thomas. Both players joined the Spurs towards the end of the season, so it makes sense that they would be more efficent in their second season.
I was a little surprised about the DRtg results. They showed that players allowed one more point per 100 posessions. I thought this would be lower since players would understand the defensive rotations better. Only five of the players actually lowered their DRtg while most increased it slightly.
The win shares showed slight improvement offensively and defensively, which is not too shocking. Overall, the win shares indicate that players contributed to nearly half a win more per season. While this is not a big amount, it is encouraging.
In the end, the numbers show that players in their second year with the Spurs are likely to experience a slight improvement in their offensive and defensive efficiency. The difference most likely won't come in their field goal percentage or points but in their overall understanding of how the team works. They will make fewer mistakes and help the offense run more efficiently, which makes sense when you think about it.
However, when I looked closer at the players that improved, it appeared to me that the jump from year one to year two was not necessarily because of better understanding of the Spurs offense but because of logical improvement that would have happened regardless of where they played. For example, Parker and Ginobili showed improvement because it was their second season in the league, and increased statistics and greater efficiency makes sense. I would also argue that Jackson's improvement was not because of greater familiarity with the Spurs but because he had raw talent that just needed time to develop.
What does this all mean for the Spurs players entering their second year with the team, Roger Mason Jr. and George Hill?
I expect Mason's basic numbers to fall because of the changes the Spurs have made. The addition of Richard Jefferson will cut into the number of shots he sees and it moves him down the pecking order on offense, which in reality moves him to his more natural role as a spot up shooter and not a creator. Since our numbers show that players improve in their efficiency, I expect his advanced statistics (PER, AST%, TOV%, etc.) to improve. Also, he will be asked to play point guard less (I hope), which means he will have to make fewer ball handling decisions and take better shots.
As for Hill, his numbers should improve across the board with Pop showing more willingness to play the youngster. Both Parker and Ginobili showed improvement in their second year, and while I'm not suggesting Hill is on level with either All-Star, he is closer to them mentally than Beno Udrih, the only other rookie in my dataset. Udrih, another back up point guard, saw his numbers decrease in year two, but Hill stronger mentally and seems to have Pop's confidence. He played well in the playoffs, when he got to play, and had a great Summer League.
Based on all of this, what do you expect out of Mason and Hill this year?