Horse racing-Gun Runner stuns Arrogate to win Breeders' Cup Classic

* Gun Runner wins from the front

* Collected second, West Coast third

* Arrogate fifth in final race (Adds quotes and details)

DEL MAR, California, Nov 4 (Reuters) - Gun Runner won the $6 million Breeders' Cup Classic in impressive fashion at the Del Mar Thoroughbred Club racetrack on Saturday, trouncing a celebrated field that included last year's winner and favourite Arrogate.

Florent Geroux piloted the four-year-old colt to a 2 1/4 lengths, wire-to-wire victory over hard-charging second place finisher Collected in front of a packed grandstand to win America's richest race.

"(I thought) he was going too fast but when I saw him pulling away, it was an unbelievable feeling," Gun Runner owner Ron Winchell said.

Up and coming three-year-old colt West Coast finished third with Arrogate fifth behind War Story.

Gun Runner's Hall of Fame trainer Steve Asmussen said he and jockey Geroux wanted to stick to the same game plan that propelled the striking chestnut horse to five wins in his last six starts.

"We wanted him away from the gates cleanly and into a nice rhythm," said Asmussen, who now has six Breeders' Cup wins, including two Classics, to his name.

"The confidence that Florent has in the horse, the way the horse has been training coming into this race, I think letting him be who he is has put him on this stage and made him undoubtedly the Horse of the Year." The 34th running of the Classic played out in front of 37,692 horseracing enthusiasts on a sunny and windy day at picturesque track in Southern California.

The win was sweet revenge for Gun Runner, who narrowly lost to Arrogate in a thrilling race at the Dubai World Cup in March.

After a poor start, Arrogate never threatened to get near Gun Runner or Collected, who battled down the stretch in the 1 1/4-mile (2 km) race.

Arrogate had hoped to join 2000 and 2001 Classic champion Tiznow as the only other back-to-back winner of the race, but it was not to be.

"He's so much better than that," Arrogate trainer Bob Baffert said after the horse's last race of an illustrious career.

"It's just really disappointing to see him go out like that because we know how great he is. At the same time, he has given us the biggest thrills in racing and I just feel sorry for the horse."

Arrogate jockey Mike Smith said he did not think Arrogate, who has lost three straight races in Del Mar, showed his best form on the oceanside racetrack, which is known for its tight corners and firm, fast turf.

"He certainly didn't run his race today. He ran only a C effort and still got beat by only five lengths," Smith said.

"It is, what it is ... I know how good he is and hopefully he'll go into the breeders' shed and make some champions." (Reporting by Rory Carroll, editing by Nick Mulvenney)