Sunderland have conceded 49 goals so far this season -- the main reason why Sam Allardyce's side find themselves in relegation trouble inside the bottom three.

Their record at the Stadium of Light is not as troubling, with only 13 goals conceded on home turf to date.

But the Black Cats are evidently vulnerable and Rooney and Martial will be looking to add to their goal tallies as United bid to keep their prospects of Champions League qualification alive.

They go into the weekend six points off the top four under Louis van Gaal, whose position remains under intense scrutiny following reports of an approach for Jose Mourinho to replace the Dutchman as manager at Old Trafford.

Rooney, who scored one of the goals in United's comfortable 3-0 home win over Sunderland in September, has netted seven times in his last eight games.

And while Martial has scored just once in seven games, the France international looks to be heading back towards top form and needs just one goal to reach double figures in his first season in England.

"The amount of ability he's got is huge. The potential is certainly there," said Michael Carrick of 20-year-old Martial.

"It's easy to forget the age he is and how little football he's actually played as well. To have such an impact at this stage, with the expectations based on him and the way he's dealt with it, has been superb.

"His performances have been very good. I think we have to understand that sometimes he might not be that shining light and have days when it's not quite happening for him, and that's understandable.

"But over time he'll improve and I've seen a big improvement already in this short time. Hopefully that trend will continue and he'll get better and better."
                  
We need six wins                  
                  
United have lost just one of their last nine games, but conceded a late equaliser in a 1-1 draw at Chelsea last Sunday that saw them slip six points behind Manchester City, who are currently fourth.

Van Gaal's side therefore have little margin for error if they are to close the gap and with the top four sides all playing each other this weekend, they must take advantage of dropped points elsewhere.

Fit-again defender Phil Jones could return after playing for United's under-21s against Norwich City on Monday, when striker Will Keane, 23, scored five times to stake his claim for a place in the senior squad.

Sunderland go into the game having sacked England international Adam Johnson on Thursday after the winger pleaded guilty to child sex charges.

Sunderland have not beaten United at home in the league for almost 19 years and Allardyce says they will have to win more games in their final 13 matches than they have in their previous 25 to have any hope of staying up.

Second-bottom Sunderland have five league victories so far, but Allardyce believes it will take six more to bridge the four-point gap to safety as they bid to extend their nine-season stay in the top flight.

"We're not quite into the territory of having to win back-to-back matches at this stage," said Allardyce, whose side fought back to draw 2-2 at Liverpool last weekend.

"But looking at it, we need six wins from our last 13 matches to get us to 38 points."