The bitter Premier League rivals are meeting for the first time in Europe as Liverpool and United look to qualify for the Champions League by virtue of winning the Europa League.
Liverpool have lost their last four Premier League games to Louis van Gaal’s side and the Merseyside haven’t beaten United since a 3-0 at Old Trafford in 2014.
However, Jurgen Klopp’s side are on a three-game winning streak in the English top-flight, whilst Van Gaal’s United outfit lost 1-0 to West Bromwich Albion at the weekend.
But former Red Devils captain Keane is confident the 20-time English champions can secure a first-leg advantage at Anfield on Thursday night.
“It is a huge game,” Keane told ITV Sport.
“The fact it is Manchester United v Liverpool, it always is no matter what is at stake.
“They’ve had a disappointing season so far. It is a hard one to call. Liverpool on the back of a couple of decent results, United really poor at the weekend.
“But I think United might just edge it.”
Enhanced odds: Get 10/1 on Man Utd to beat Liverpool
Keane was part of Sir Alex Ferguson’s squad that won the Champions League in 1999.
The former Republic of Ireland captain won seven Premier League titles during his Old Trafford career.
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