Manchester - Vincent Kompany's return from a calf injury cannot come soon enough for a Manchester City side who have continued to look defensively vulnerable in his absence.
The captain missed an eighth successive match with a calf problem as City lost 2-1 at Arsenal on Monday, a result that has left them six points adrift of leaders Leicester City going into the Christmas programme.
Kompany, though, has returned to full training this week and is in contention to play some part against Sunderland at the Etihad Stadium on Saturday.
A quick glance at the statistics will show why City's supporters are so keen to see him return.
In the eight league fixtures in which he has played this season, City have conceded just one goal.
In the nine he has missed, they have let in 18. Manager Manuel Pellegrini has played down the suggestion that his defence cannot function without the Belgium international, but his influence is undeniable.
"Of course, you always miss good players," Pellegrini said.
"He's the captain here and if he doesn't play, then he is an important player we don't have in our squad. It is the same with Sergio Aguero and David Silva.
"But the most important thing about this team is that we are involved in all four competitions and do not just depend on one player. All of them are very important."
Striker Aguero's absence was also keenly felt after he picked up a heel injury against Southampton in late November.
He returned against Arsenal, but still did not look fully fit, and Pellegrini must decide if he is ready to start two matches in four days, with a trip to Leicester to come on Tuesday.
Wilfried Bony, who has been Aguero's stand-in, will hope to start at least one of those matches.
City's performance at Arsenal did little to quell ongoing speculation about Pellegrini's long-term future at the Etihad.
It is widely expected that he will be replaced at the end of the season by Pep Guardiola, who announced last Sunday that he will leave Bayern Munich when his contract expires in June.
"The speculation started last year," Pellegrini said. "Sometimes it's true, other times it's not true. But it's part of the profession.
"You can read and hear different things, but for me it's important to think about your work, and trying to win."
His opposite number, Sam Allardyce, has worries of his own, admitting that he is "massively concerned" about the five-point gap between second-bottom Sunderland and safety.
Three consecutive defeats leave the Wearside club in danger of losing touch with the clubs above them in the fight for Premier League survival.
Fellow strugglers Bournemouth and Newcastle United have picked up crucial victories in recent weeks, and Allardyce said: "We're deeper in the mire with 12 points from 17 games and I'm massively concerned at the distance to the teams above.
"We had back-to-back wins and looked like we were going to move away from the bottom, but then we go and lose three on the trot."
Influential trio Younes Kaboul, Lee Cattermole and Seb Larsson are sidelined through injury.
Allardyce will be forced into at least one more change to the side soundly beaten 3-1 at Chelsea, as former City midfielder Jack Rodwell is suspended after reaching five bookings.
Sunderland, who have never won at the Etihad, go in search of their first victory on City soil for almost 18 years.
"In the position we're in, you always have to try to score the first goal," Allardyce added.
"It's a bizarre league this year, because more teams are winning away from home than ever before, and more teams at the bottom are beating teams at the top."