The Rutgers-bound guard - ranked 55th in the Rivals 150 - scored 18 of his 21 points in the fourth quarter, and hit the game-winning three at the buzzer to help the Playaz eek out an 86-85 victory.
New Heights, a team made up entirely of freshmen and sophomores, outplayed the number two-seed Playaz, but Rosario's brilliance, and some costly missed free throws, allowed the win to slip away.
Early on, the young but big New Heights team proved that it wouldn't be intimidated by the Seniors. Every time Playaz guard Jiovanny Fontan drove into the lane, he was flattened. Unfortunately for New Heights, Fontan went 6-for-6 from the free throw line in the first quarter en route to 10 first quarter points. The game was knotted at 18-18 after one.
A.J. Rogers hit a long baseline jumper off an assist from Fontan to begin the second, but New Heights then made its first major push, going on an 8-0 run to take a 26-20 lead. Fontan, however, eventually guided the Playaz back to a deadlock with New Heights, and the young guns led just 35-34 at half.
The Playaz took a brief lead in the third, 39-37, on a three by Fontan, but the rest of the quarter belonged to New Heights. Jayvaughn Pinkston scored six points to key an 11-4 New Heights run, capping the stretch with an emphatic fast break jam.
Chris Gaston hit a long transition jumper to bring the Playaz within 48-45, but a pair of New Heights threes pushed the lead to nine. The Playaz eventually cut the lead to six, but big man Devon Collier nailed an unexpected pull-up three for New Heights to make it 59-50 after three.
The Playaz scored the first five points of the fourth to trim the New Heights advantage to four, and the teams traded baskets to put the score at 61-57. Devon "Fatty" McMillan then sunk a pair of tough jumpers for New Heights to stretch the lead back to eight.
New Heights led 75-67 when Pinkston came from nowhere to swat a lay-up attempt by Playaz guard Travon Woodall. Gaston, however, followed the block with a bucket, and Woodall scored on the next possession to make it 75-71 with 2:02 remaining.
Freshman guard Corey Edwards canned a pair of free throws for New Heights, but Rosario, showing veteran savvy, then got himself to the line for three freebies after getting his defender in the air on a pump fake.
Rosario dropped in all three free throws, but New Heights once again opened up to lead 81-74. Pinkston converted a three-point play to put New Heights ahead 84-78 with 41 seconds remaining, coming close to putting the coup de grace on a Playaz comeback.
Rosario though, hit a contested three with 26 seconds to go, splitting the New Heights lead.
McMillan was then fouled, and the Lincoln sophomore missed both free throw attempts. After Playaz guard Alberto Estwick missed a game-tying three, McMillan was sent back to the line.
Again, however, McMillan bricked both free throws, and Playaz forward Madut Bol was fouled on the rebound. Bol, son of former NBA'er Manute Bol, made both free throws with 11 seconds left to make it 84-83, New Heights. The Playaz, sensing a pattern, made sure to foul McMillan on the inbound.
This time, McMillan managed to make one of two, but the Playaz had been given enough daylight to take advantage.
Rosario drove past half court and pulled up for a long three-pointer with six seconds to go. The three dropped in, and a desperate heave by New Heights at the buzzer went astray, giving Playaz Seniors an 86-85 win.
The Playaz - undoubtedly lucky to escape the second round - move on to Sunday's quarterfinals, where they'll take on United Brooklyn, winners over NYABC, at 11:45 a.m.
Rosario's 21 points led the Playaz, while Woodall and Fontan each added 17 points, and Eastwick scored 15 points. Collier paced New Heights with 20 points, McMillan finished with 18 points and Pinkston dropped 15 points.
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