There was a time when a racing fan could walk into a Maryland track on opening day with the sure knowledge that nothing would be changed from the previous year. In fact, some of the same dirt was likely to be present.

But since Frank DeFrancis bought Laurel Race Course, he has promised and delivered plenty of improvements. Yesterday's opening-day crowd of 8,719 was greeted by a new announcer, a new form of betting, improvements in the physical plant and improvements in the racing program.

The biggest change of all, the Sports Palace, wasn't quite ready. DeFrancis hopes he will be able to open the $2 million facility by the end of the week. But an early peek confirmed the notion that it's going to be a knockout -- a facility worthy of any top race track in the country.

With the opening of the Sports Palace deferred, the most conspicuous change at Laurel was the replacement of long-entrenched announcer Dick Woolley by Robin Burns, who calls the harness races at Freestate. Burns could not help be an improvement, although the first stakes races he called in his new job, the first division of the Sports Palace Handicap, contained enough flubs to evoke memories of Woolley.

Laurel flubbed a bit, too, in its introduction of a new form of exotic wagering, the Double Triple, which requires the bettor to pick triples in the fifth and seventh races. But there was no explanation of the wager in the program, and Burns had to come onto the public address system to offer "clarifications" such as this: "If you pick the first half of the Double Triple, you will receive 50 percent of the triple payoff when you collect."

This didn't mean anything, but one seller said, "There was some confusion but people started getting the hang of it fast." The Double Triple promises to be a very popular form of super-exotic wagering. A total of $37,254 was bet on it yesterday (as compared with $4,862 on the Pick Six). One customer mastered its complexities well enough to collect a payoff of $13,970.

Another innovation at Laurel was the introduction of extra information in the program for races between 2-year-olds. In these bewildering events, which are often full of first-time starters, Laurel tells its customers the birth date of the horse and the stud fee of the stallion and also indicates dams who have produced winners and stakes horses.

Other improvements include nicely appointed front-row box seats and repairs to potholes in the parking lots. "We've tried to do a little bit for everybody," DeFrancis said.

The track's $2.1 million stakes program started yesterday, with two divisions of the $35,000 Sports Palace Handicap at 5 1/2 furlongs on the turf. Whoop Up led all the way to win the first division by a nose over Bryantown. Chas Conerly rallied to beat Milady's Eagle by two lengths in the second division, equaling the track record of 1:03 2/5.