Five-year-old Host improved to three-for-three on the Gulfstream Park turf, wearing down pacesetting Navesink River in the closing strides to win the $100,000 Mac Diarmida Handicap (gr. IIIT) Sunday.Calamity struck on the far turn of the 1 3/8-mile event when the gelding In Hand fell while making a big move in the 12-horse field, throwing jockey Gary Boulanger. Rider Eddie Castro also fell when his mount, Irish-bred Macaw, hit the fallen horse. Last Answer was forced to check to avoid the accident and was eased in the stretch by jockey Patrick Husbands.Gary Boulanger was taken to the trauma unit of Memorial Hospital in nearby Hollywood. He was stabilized on the track by paramedics. Later, Boulanger was reported to be in critical condition in the hospital's intensive care unit.In Hand was euthanized. Casto and Macaw escaped without serious injury.With Javier Castellano aboard, 11-1 Host tracked Navesink in second shortly after the start of the 1 3/8-mile affair, edging ahead at the end to win by a neck in 2:12 4/5. Favored Burning Sun finished three-quarters of a length farther back in third, with Change Course fourth.Taking over the lead from Burning Sun shortly after the break, Naveskink River, ridden by Jorge Chavez, settled into comfortable splits of :25 2/5, :50 1/5, 1:15 and 1:38 3/5 for the mile. Host increased the pressure on the leader on the far turn as Gigli and Burning Sun moved into contention. Navesink River jumped marks in the final sixteenth.Burning Sun, who carried top weight of 118 pounds and spotted the winner four pounds, soon passed Gigli for third. Jockey Jerry Bailey had a clear shot at the leaders on the outside, but could not make up much ground through the lane.A Kentucky-bred chestnut son of Tabasco Cat-Rare Bird (Rahy), Host notched his first career graded stakes victory for trainer John Kimmel and owners Caesar Kimmel, Philip J. Solondz and C.G. Zoe Stable. Host was coming off a fourth-place finish in the John Henry Stakes at Meadowlands Oct. 29, just a half-length behind the winning Macaw. Castellano rode Host to victory in an optional claiming/allowance race at Saratoga in September."I knew he liked to be close to the pace and he likes to fight for the lead," Castellano said. "He was off for three months but the trainer got him ready for a race this long."Host captured back-to-back allowance races on the Gulfstream grass last spring at 12 and 11 furlongs, respectively. Sunday's victory was his fifth in 19 career starts and increased his earnings to $237,280."He got some time off after that last start that wasn't supposed to be," Kimmel noted. "He got a post-race butt shot and the veterinarian shot him outside the vein so he swelled up real bad and missed about a month. But he's come back well. We thought we had a nice horse at that time and now we still do." Faisal Al-Suwaidi bred the winner, who paid $25, $11.60 and $6.40. Navesink River returned $12.80 and $7.60. Burning Sun was $2.80 to show.After Change Course came, in order, Swagger Stick, Broadway View, Scooter Roach, Gigli, Rio Guapore, and Last Answer. Tap Day, Colonial Bay and Final Prophecy were scratched.