The chairman of the Maryland Racing Commission's thoroughbred board confirmed for the first time yesterday that Large As Life ran under the name of stakes-winning Dare To Command in two races at Pimlico last summer.

"There is a possibility of a slipup or a mistake," said Robert Banning, the chairman. "We haven't found anything which would have (indicated) an intentional substitution."

Banning said he would call a meeting of the board later this week to determine what, if any, penalties should be imposed. That Large As Life probably had run as Dare To Command was first reportd in The Washington Post in January.

Banning said he already has ordered that horses now be identified by two persons instead of one.

Banning's remarks followed a meeting of Maryland's racing stewards, who were investigating the possibility that the wrong one of the two stallions owned by Harlan (Sandy) Sanders of Wilmington, Del., had been raced at Pimlico.

Banning said that since he was not present at the steward's meeting he did not want to discuss specifics of the incident.

Sanders and the trainers, King T. Leatherbury, have denied there was a deliberate switch and Pimlico identifier Jimmy Rowan has said his records show Dare To Command ran at Pimlico on May 27 and June 24.

New York Jockey Club registrar Alfred Garcia said he believes the horses were mixed up, possibly by a groom, when they were sent to a farm together to rest in the last half of 1977.

Although the horses resembled each other physically -- with the exception of a white mark on one's nose -- their identities should have been established clearly by the tattoos on their lips.

The mix-up was discovered when an Arkansas breeder, who thought he had paid stud fees for Large As Life, sent blood samples to the Jockey Club to certify that horse as a working stallion.The Jockey Club notified the breeder that his horse was Dare To Command.

Dare To Command, son of the Bold Ruler colt Bold Commander. had earned $146,000 in stakes races. He had not been raced for almost 13 months when he supposedly was entered at Pimlico. The first time out, at 7-to-2 odds, "Dare To Command" was beaten by 22 lenghts. The second time, he went off at 29-to-1 odds and was beaten by 30 lengths.