Niatross will try to become the first Triple Crown pacing champion in 10 years tonight when he meets six 3-year-old rivals in the Messenger Stake in Westbury, N.Y., and in the opinion of Del Miller, a Hall of Fame driver-trainer, "Nobody's going to beat Niatross."

The Roosevelt Raceway handicapper doesn't think any of Niatross' Messenger opponents pose a serious threat to the son of Albatross, driven and trained by co-owner Clint Galbraith. Niatross is the early 1-to-9 favorite to win the mile race over Roosevelt's half-mile track and become the first winner of the Cane Race, Little Brown Jug and Messenger since Most Happy Fella in 1970. The co-second choices at 8 to 1 are Tyler B and Trenton Time.

"If you aksed an artist to paint a horse, and wanted him to pain the perfect animal, you'd get a picture of Niatross," said the 66-year-old Miller.

Niatross won all of his 13 starts as a 2-yar-old and this year has 16 victories in 18 races. He won the $1,0011,000 Meadowlands Pace after breaking and barely gaining the final with a fourth-place finish in a qualifying heat. He also set world race records for any age of 1:52 4/5 on a mile track at Syracuse, N.Y., and of 1:54 4/5 on a half-mile track in winning the second heat and the race in the Little Brown Jug at Delaware, Ohio. He also set a time-trial record of 1:49 1/5 at the Red Mile in Lexington, Ky., Oct. 1.

Meanwhile, the horse's co-owners have been ordered to surrender the horse in January to a breeding syndicate that plans to retire him. Bergen County Superior Court Judge James Petrella ruled in favor of a suit brought by the 27-man syndicate and ordered Galbraith and Elsie Berger to give up the horse by Jan. 1, 1981.

Berger and Galbraith want to continue racing the horse. But the syndicate, headed by Louis Guida, prefers to retire the horse to stud as soon as possible rather than risk serious injury. Berger and Galbraith sold a 50 percent share in the horse to the syndicate in October 1979 for $2.2 million. Included in the sale agreement was a provision granting the syndicate sole authority for selecting a stud farm for Niatross at the end of his racing career or after his third year of racing, whichever came first.