Manchester City's centre-backs Ruben Dias and John Stones both struck as the Premier League leaders beat West Ham 2-1 on Saturday, while West Brom enlivened the battle to beat the drop with a controversial 1-0 win over Brighton in which the Seagulls missed two penalties.
Pep Guardiola's men are now 13 points clear thanks to a 20-game winning run in all competitions that has seen them close in on an unprecedented quadruple of trophies. For the first time in recent weeks, City showed signs of fatigue, though, and needed the dominant centre-back pairing that has been a huge part of their success defensively this season to also make their mark at the other end.
"After 10 or 15 minutes today we realised we were not going to paint anything beautiful," said Guardiola.
"When you play a lot of games - in the league and then the Champions League - this is normal. We were lucky to get all three points."
Kevin De Bruyne made just his second start since returning from a hamstring injury and the Belgian's teasing cross was powered home by Dias for his first City goal since joining from Benfica in September.
City had kept eight clean sheets in their previous 10 league games, but West Ham showed why they are fourth and pushing to edge out the likes of Liverpool, Chelsea, Tottenham and Arsenal to qualify for next season's Champions League.
"I'm really disappointed we didn't get a point," said West Ham boss David Moyes.
"It was a terrific performance. We came here and tried to match a top side - and for long periods we did."
Michail Antonio had already threatened an equaliser by hitting the post before he did level by tapping home Jesse Lingard's mishit shot just before half-time.
But City's determination to keep winning shone through in the second-half as Stones smashed home Riyad Mahrez's pass for the winner on 68 minutes.