Dixieland Band, who had failed to win in four starts this year, raced to the lead with three-sixteenths of a mile to go yesterday and won the $227,500 Pennsylvania Derby by a neck at Keystone Race Track in Cornwells Heights, Pa.

Dixieland Band, a brown colt ridden by William Passmore and owned by Mrs. Bayard Sharp, edged Jacques Tip in a stride-for-stride stretch duel to capture the $136,500 first-place purse in 1:49 2/5 over a fast track in the 1 1/8-mile race. Intention finished third, 2 3/4 lengths behind Jacques Tip, with Bet Big fourth in the field of nine. Megaturn, the 4-to-5 favorite who had won four of his last five races, was sixth.

The race lost most of its luster Sunday when trainer Bill Boniface scratched Preakness winner Deputed Testamony. Boniface also scratched Parfaitement. Also scratched was Current Hope, winner of the Flamingo Stakes at Hialeah . . .

Star Choice, a 17-to-1 shot, overtook Tough Critic in midstretch at Belmont Park in Elmont, N.Y., to win the $242,000 Metropolitan Handicap by 1 1/2 lengths.

Star Choice, owned by Frances A. Genter and trained by John Veitch, carried 113 pounds, including Jorge Velasquez, to a 1:33 4/5 clocking over the muddy surface, only a fifth of a second off the stakes record. Tough Critic, who went off at 21 to 1 with 110 pounds, went on to finish second under Don MacBeth. John's Gold, carrying 111 pounds and Antonio Graell, finished third, another 3 3/4 lengths back. Favored Fit to Fight never was in contention.

Star Choice earned $145,200 and returned $36.00, $16.20, and $10.20. Tough Critic paid $18.40, $9.00. John's Gold paid $3.60.

August Belmont's Caveat, expected to be among the top contenders in the upcoming Belmont Stakes, prepped for that engagement by easily winning a $32,000 allowance. Caveat split horses in midstretch and won the 1 1/16-mile race going away in 1:41 1/5 . . .

Debonair Dancer defeated Princess Roberta by one length in the inaugural running of the $33,450 Flocarline Handicap at Pimlico Race Course in Baltimore. The favorite in a field of six, Debonair Dancer, ridden by Jack Kaenel, completed the 1 1/16 miles in 1:43 1/5. Princess Roberta finished three lengths ahead of As Hot As and paid $4.20; $2.80 and $2.60. Princess Roberta paid $3.60 and $3.40 and As Hot As $4.80.