The 20-time English champions make the short trip to Merseyside to face their bitter rivals, who are just two points behind fourth-placed United.
If they win on Sunday then I think they can maybe start looking at catching Manchester City
The Red Devils face a difficult end to the season, which includes games against Premier League leaders Chelsea, derby rivals Manchester City and their FA Cup conquerors Arsenal.
However, former United defender Neville reckons victory over Liverpool can propel Louis van Gaal’s side to a second-place finish ahead of the Citizens and the Gunners.
Neville told talkSPORT: “I said at the start of the season I had a feeling Manchester United were going to finish second and I’m going to stand by that.
“[The win over Spurs has] given every Manchester United fan a massive lift. It was a proper Manchester United performance and I think this Sunday [against Liverpool] will be a defining moment.
“If they win on Sunday then I think they can maybe start looking at catching Manchester City, who are only two points ahead. If they lose then Liverpool are really building up a head of steam, Tottenham are playing okay too and becomes more difficult for them to finish in the top four.”
Liverpool kept pace with their top-four chasing rivals thanks to a 1-0 win at Swansea City on Monday night.
The Reds can hoist themselves above the 20-time English champions with victory on Merseyside on Sunday afternoon.
United still have to face local rivals Manchester City, leaders Chelsea, Everton and Arsenal before the end of Van Gaal’s first season in charge at Old Trafford.
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