Hoey closed with 7-under-par 65 to finish at 17-under 271. Damien McGrane, who either led or shared the lead for three rounds, shot 70 and was runner-up.
Manassero needed to win to enter the top 50 in the world rankings to make the Masters, which starts April 5. He entered the final round tied for the lead but shot 72 for 276. He bogeyed No. 1 and double-bogeyed No. 8.
The 18-year-old Italian competed in the 2009 Masters as the British amateur champion.
“I would have loved to be going to Augusta for a first time as a professional,” he said. “But I will go now to Sicily this week and concentrate on winning the Sicilian Open.”
CHAMPIONS TOUR: In Sacucier, Miss., Fred Couples made an 8-foot birdie putt on the final hole to win the Mississippi Gulf Resort Classic.
Couples started the day tied for the lead with Jeff Sluman, but moved ahead with a birdie on the first hole. He led the rest of the day until the 17th, when his bogey dropped him into a tie with Michael Allen.
Couples shot 3-under 69 in the final round and finished at 14-under.
LPGA TOUR: In Carlsbad, Calif., top-ranked Yani Tseng won the Kia Classic for her second consecutive LPGA Tour title and third in five events this year, closing with 2-under-par 70 for a six-shot win.
The 23-year-old Taiwanese star became the second-youngest player to reach 15 LPGA Tour victories. Nancy Lopez was 22 when she reached the mark.
Tseng finished at 14-under 274 on La Costa’s Legends Course.
NATIONWIDE TOUR: In Broussard, La., Casey Wittenberg won the Louisiana Open for his first Nationwide Tour title, closing with 6-under-par 65 for an eight-stroke victory.
The 27-year-old former Oklahoma State player finished at 24-under 260 at Le Triomphe Country Club.
Augusta’s Scott Parel shot 67 and tied for 28th at 275.