Syracuse center Arinze Onuaku will not play Thursday against Butler in the West Regional semifinal. Orange coach Jim Boeheim says the 6-foot-9 center is doing better but will not be available for the Butler game. Onuaku has an injured right quadriceps. Boeheim didn’t speculate on whether Onuaku would be able to play Saturday if the team advances. Onuaku averaged 10.5 points and 5.1 rebounds this season for Syracuse, which defeated Vermont by 23 and Gonzaga by 22 points without the center in the first two rounds of the ncaa tournament.