Manchester City rode its luck in beating Crystal Palace 1-0 to move provisionally top of the English Premier League, while Manchester United won by the same score at Norwich to stay in the title picture on Saturday.
The Manchester giants dipped into their reserves for a second game in three days and produced disjointed displays that were rescued by second-half winners.
Edin Dzeko's 66th-minute goal maintained City's record of scoring in every home game in more than three years — a run of 60 matches — and lifted the team two points above Arsenal, which plays Newcastle on Sunday.
Danny Welbeck came off the bench to score a fortuitous winning goal for United in the 57th minute at Carrow Road, earning the champions — missing injured striker Wayne Rooney — a fourth straight league win.
Hull thrashed third-to-bottom Fulham 6-0 and last-place Sunderland scored twice in the final seven minutes to draw 2-2 at Cardiff, which fired manager Malky Mackay on Friday.
West Ham will also be in the bottom three going into 2014 after twice squandering a lead in a 3-3 draw with West Bromwich Albion, and Aston Villa drew 1-1 with Swansea.
City's 10th league win from 10 matches at Etihad Stadium in this campaign was far from straightforward, with Manuel Pellegrini's decision to make six changes from the 2-1 victory over Liverpool on Thursday disrupting City's attacking rhythm.
Most pundits' title favourites relied on Dzeko's finish from Jesus Navas' cut-back to eke out three points against a Palace side that has tightened up since the appointment of defensive-minded Tony Pulis as manager in November.
"It was a hard game, maybe the toughest at this stadium in the Premier League this season," said Dzeko, who scored his 50th City goal. "It was the last game of 2013 and we wanted to finish with a win."
City goalkeeper Joe Hart played with a gash under his left eye after a collision with Palace striker Cameron Jerome in the first half, but that didn't stop him producing some fine saves after the break to preserve City's perfect home record.
"I think the team that wants to win the title must have different faces," said Pellegrini, whose team is unbeaten in its last 11 games in all competitions.
United was without Rooney and Robin van Persie for the first time this season, and manager David Moyes started Welbeck as a substitute for his and the team's third game in eight days.
The England striker's halftime introduction energized United and he pounced when a clearance from Ryan Bennett deflected into his path, rounding goalkeeper John Ruddy to slot home.
"He changed the game when he came on," Moyes said. "He is doing very well, and we need everybody to chip in with goals when Wayne Rooney and Robin van Persie are out."
United is provisionally sixth in the standings, two points off the top four.
Hull's thrashing of sorry Fulham was notable for the eye-catching celebration by Tom Huddlestone, who marked his first goal since 2011 by letting club physio Rob Price cut off a piece of his hair on the sideline. The midfielder had pledged not to cut his hair until he scored again.
Fulham has looked an improved side under new manager Rene Meulensteen but this defeat — its worst in the Premier League era — was a major setback against a team which has often struggled for goals this season.
"I'm shocked," Meulensteen said. "I don't know if there was something in the tea. I did not see that coming and the players did not see that coming."
All of Hull's goals came in the second half, with captain Robert Koren scoring twice and Ahmed El Mohamady, George Boyd and Matt Fryatt also netting.
West Ham was denied victory by Saido Berahino's 69th-minute goal at Upton Park.
Former France striker Nicolas Anelka scored twice for West Brom and appeared to celebrate his first by performing an anti-Semitic salute used by French comedian Dieudonne M'bala M'bala. Jewish groups in France have linked the "la quenelle" gesture — which they claim is a Nazi salute in reverse — to anti-Semitic incidents in the country.
"It is dedicated to a French comedian he knows very, very well," West Bromwich Albion coach Keith Downing said of Anelka's celebration. "He uses it in his act and I think speculation (that it is anti-Semitic) can be stopped now, it is absolute rubbish really."