Sami Hyypia has resigned as manager of Brighton and Hove Albion just six months into his tenure at the Amex Stadium.
The former Liverpool defender took over from Oscar Garcia on a three-year contract in the summer, but leaves with the Seagulls in the Sky Bet Championship relegation zone after winning just one of their last 18 league games.
The 41-year-old Finn, who previously managed Bayer Leverkusen, saw his side draw 1-1 with Wolves at the weekend after conceding a late equaliser, with their next fixture at home to Reading on Boxing Day.
Hyypia's assistant Nathan Jones will take charge of the team on Boxing Day.
In a statement club chairman Tony Bloom said: "Sami offered his resignation, and we reluctantly accepted earlier today.
"Sami has worked extremely hard since joining the club last summer. Despite some good performances, including most recently at Wolves, results haven't gone as well as we all had hoped and expected.
"Sami is an incredibly honourable man. He remains a hugely respected and very popular figure at our club. He has decided to step down for the benefit of the team and the club.
"We are all very disappointed, but we respect Sami's decision and we all wish him well for the future."
Brighton lost their opening two league games this season but then recorded back-to-back victories before embarking on their current dismal run of league form - with a 1-0 win over Wigan last month representing their only Championship success since August.
A run to the fourth round of the Capital One Cup provided some relief, but that ended with a 2-0 loss at Tottenham, and a 1-0 home defeat to fellow strugglers Millwall 10 days ago left Hyypia admitting his future at the club was uncertain.
"At the moment, straight after the game, I feel very frustrated," he said at the time. "To answer that question I need some time. Usually I'm not a quitter, I'm a fighter.
"I can understand the fans' reaction, I don't expect to be patted on the shoulder and told 'well done' with how things are going. I think that's normal, some of the fans are getting impatient and shout things, it doesn't help anyone but you can't control it.
"When you take this kind of job, I've always been prepared for everything, I'm not afraid of anything happening. When you take this job sometimes it doesn't go your way, but in my mind I'm ready for it."
Former England striker Darren Bent's 10th-minute strike at Molineux on Saturday looked like providing some welcome respite for Hyypia, but Danny Batth's leveller two minutes from time was the final straw.