Tatjana Smith, Erin Gallagher and Pieter Coetzé all took gold in their 50m disciplines on Monday evening as the SA Swimming Championships got under way.

Erin Gallagher broke her national record in the 50m butterfly event on Monday evening at the South African Swimming Championships with a time of 25.59 seconds -- edging her 25.66 seconds at the World University Games at the end of last year.

The first day of action at the SA Swimming Championships was all about the short sprints, with all the single-lap, 50m events taking place on Monday at Newton Park Swimming Pool in Gqeberha.

South Africa's premier swimmers were on show and the spectators weren't disappointed as Olympic champion Tatjana Smith -- formerly Schoenmaker -- and Commonwealth Games gold medallist Pieter Coetzé put on a show in the 50m breaststroke and 50m backstroke, respectively.

Of all the 50m events, only the freestyle is an Olympic event, so most swimmers used day one of the national championships as a warm-up for the longer events in the same discipline -- aiming for Olympic qualification.

"I'm not over the moon with the time," 19-year-old Coetzé said. "It would have been very nice to go faster than that, but it's a 50m so I'm just glad I could get a warm-up swim on day one going into the rest of the meet.

"I...