Newcastle have terminated the contract of rugby director Steve Bates with immediate effect.
The announcement comes just four days before the Falcons conclude their Guinness Premiership campaign against Wasps.
Newcastle currently lie 10th in the Premiership, nine points above Worcester, who are guaranteed to finish bottom. The Falcons have won just six of their 21 league games this term.
The club said it had been decided to end 46-year-old Bates' stint in charge following an internal review.
He rejoined Newcastle as rugby director in 2007, having originally left Kingston Park four years earlier following a successful spell as head coach under Rob Andrew's Premiership title-winning regime.
Bates said: "I am disappointed at the outcome of this review, but I am proud of what has been achieved this season in a very competitive environment.
"I would like to thank the players and all of the back-up staff for their support and effort.
"I would also like to thank my wife and family for their fantastic support, loyalty and encouragement during this time."
Falcons chairman Dave Thompson added: "We would all like to express our thanks to Steve for his contribution during his time as director of rugby, and wish him every success in the future.
"With immediate effect, first team coach Alan Tait will now take charge as head coach, reporting into chief executive David Bell.
"Alan will be undertaking a review of the playing, coaching and support structure, and announcements relating to that review are expected shortly."
Newcastle reached the quarter-finals of this season's Amlin Challenge Cup, but they were destroyed at home by Cardiff Blues, and it took a thrilling victory over Sale Sharks 11 days ago to guarantee their Premiership survival.
Bates, a former scrum-half who was capped by England in 1989, becomes the third high-profile figure to depart a Premiership club in little more than a week.
Former Wales coach Mike Ruddock left Worcester after their relegation was sealed with a narrow defeat against Leeds Carnegie, while England World Cup winner Jason Robinson departed his role as head coach at Sale.
The Sharks have brought in ex-New Zealand All Blacks forward Mike Brewer, although Kingsley Jones retains his role as rugby director.
Newcastle have yet to announce any major new signings for next season, but among those players leaving Kingston Park are All Blacks prop Carl Hayman, who will link up with former Falcons fly-half Jonny Wilkinson at Toulon, wing Tom Biggs and young fly-half prospect Rob Miller.Reuse content