Chalmers ran 49.10s in the 400 hurdles as he looks to get down to the Olympic standard of 48.70s.
It was another step forward after recording his quickest season opener in Florida at the end of March (49.54s), and came from a tricky inside lane draw.
Chalmers’ best is 48.88s from May 2022 run in Belgium, where he returns on 26 May.
Pictured top: Alastair Chalmers winning gold at the Guernsey Island Games last year.