United have won four consecutive games, each by a three-goal margin. However, Saints are unbeaten in three games, which included an impressive win over Manchester City.
“Like any of our opposition's players, we will always look at clips before the game to see who we are up against and to assess their strengths and weaknesses," he said.
“(Mason) Greenwood will be no different. We'll look at him and we'll look at the rest of their players and see where we can go.
“They have had some really good results since the break but then they've got some brilliant players, so they are always likely to pick up results.
“On their day they can beat anyone in this league and we know we have to go there with the right attitude and the right mindset.
“We'll have to give it our all and if we do that we'll have a great chance.
“We are on a good run, three unbeaten, and we want to keep this going for as long as possible. We know it's going to be a tough game at Old Trafford, but we are full of confidence.
“If we play and fight like we did against Everton then we are in with a real shout of getting a point or three."