Liverpool win at Anfield in the Premier League for the first time since mid-December with a 2-1 win over Villa.
The Reds reverse the opposite of the fixture in October where Villa won 7-2.
Watkins grabbed the lead for Villa in the first half, when his shot bounced under Alisson.
Liverpool had a goal disallowed by VAR minutes later for a tight offside when Roberto Firmino scored from Diogo Jota pass in the build-up.
Salah equalised with a tap-in close range header and just about had enough in the end to claim the way after the break before Trezeguet rattled the post at the other end.
In added time, Alexander-Arnold latched onto Cash’s clearance and curled his effort into the far bottom corner to earn the three points.
And what a contribution to the debate over whether he should win a place in the England Euros squad from Trent Alexander-Arnold – a blinding winner at the end.
It’s a win of real significance for Liverpool and their first in nine league matches at Anfield.
Liverpool make the huge jump into fourth place with these three points, but Chelsea, West Ham and Tottenham below can leapfrog over with a win each, who are still yet to play this weekend.
Now they look to their Champions League quarter-final second leg against Madrid on Wednesday.
As for Villa, they stay in 10th after Leeds United’s win earlier and they face another tough test in Manchester City next time out.