Head coach Royce Simmons has left St Helens with immediate effect after the club's worst-ever start to a Super League season.
Simmons' men lost 12-8 at Bradford on Saturday evening as the Bulls condemned Saints to their worst league run for 23 years.
That defeat meant Saints have taken just one point from their last five outings, leaving them sitting outside the top eight in the standings.
The loss at Odsal proved the final straw for the four-time Super League champions who have now opted to part company with their Australian coach after less than two years in charge at the club.
St Helens have confirmed that head of high performance, Mike Rush, will take temporary charge of first-team affairs and will be assisted by Kieron Cunningham who has been appointed assistant coach.
Explaining the decision to dismiss Simmons and his assistant Kieron Purtill, Saints chairman Eamonn McManus told the club's official website: "Our season has got off to a difficult start and it is best to make change sooner rather than later.
"We have every faith in Mike Rush and Keiron Cunningham. They each know the club inside out and have all the experience together to take us forward.
"I would like to go on record to pay genuine tribute to Royce Simmons. He is a fantastic person, and of absolute character and integrity, who has given everything to the club.
"I am sure that everyone at the club joins me in thanking him sincerely for all his work and dedication and to wish him and his family well for the future.
"Our sentiments are the same with Kieron Purtill. Force of circumstance has reconstituted change."
Simmons - who previously had a spell coaching in England at Hull in the 1990s - took over at Saints at the start of last season and led the club to the Grand Final in his first campaign in charge, losing to Leeds at Old Trafford.
He led the club in a total of 36 games; winning 21, losing 11 and drawing four of his matches at the helm.
