So, is Elton Brand scoring negative 10 points, or will it be Varejao? 
A 30/20 split (for 48) at the center position is more than fair considering Brand's last 3 games v Howard. And I think 25/15 is just as fair considering Thabo will only be giving you ~5 a night. It's not 25, but it could be depending on the play of Rubio and the defense by Irving.
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Since Rubio shoots somewhere between 30% and 35% from the field, and declined consistently as the season went on, I'm pretty sure that Irving can consistently outscore him. Kyrie Irving was a savant his rookie season. Rubio was a good passer who couldn't throw a rock into the ocean.
I'm just going to let ESPN help me out here. Rubio was on par with what Irving was doing for a while, just not in the same way. Obviously Rubio slowed and regressed a bit but let's not cut the kid from the roster yet.
Rubio was known as a closer because as the game went on, he got better. When his season came to an end, his 71 fourth-quarter assists were the most of any player in the NBA, rookie or not.
But Rubio's impact was about more than just passing. Rubio notched 12 games with at least 10 points and 10 assists, trailing only Steve Nash (18) and Deron Williams (14).
Had he finished the season with enough games to qualify, Rubio's season averages (10.6 PPG, 8.2 APG, 2.2 SPG) would have put him in exceedingly rare company. He would have joined Phil Ford, Mark Jackson and Tim Hardaway as just the fourth rookie in NBA history to reach those season thresholds.
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No offense meant, but that's kind of silly. Irving just needs to be Irving. 18 to 25 points, extremely efficient, clutch baskets.
Nobody winks at me and calls me silly in one post and gets away with it Roy. Not after that one time.
I don't think it's outside the realm of thought to question if a kid going into his second year, with a completely different role, will be able to bump his scoring by more that 5-7 more points while maintaining the same efficiency. To ask that of Irving without considering progression for Rubio, despite what he accomplished, is a lot.