Yes Liverpool must win this match and beat Southampton, but it won't be easy for Liverpool, Southampton are in the relegation zone will try very hard to survive. My opinion the score will be thin but southampton can't scored in this match, because Liverpool are too strong at home, even also Manchester City can't scored.
It's not because Liverpool is strong on their own home, but they're very lucky. Manchester City was dominate the match and they've shots on target for many times, but it's still not make at least one goal. Southampton can only make draw at their best because they don't have any capabilities to beat the top clubs.
If we look at the current performance of Newcastle and Chelsea, Newcastle is ideally the favorite team to win the next match. In the last 5 matches, Newcastle won 4 matches and got 1 draw. While Chelsea only won 1 match, got 2 draws, and got 2 losses. Moreover, the match will be held in Newcastle home, they must have extra motivation to win the match. To be honest, I don't see a chance for Chelsea to get a point in this match, their game looks very bad lately.
It's also because Newcastle play in their own home, but the odds doesn't really far. Currently the odds for Newcastle is @2.25 while odds for Chelsea is @3.20, I think it's really worth to bet Newcastle since their past four win streak and the odds quite juicy, usually the odds for strong club would be less than @2.00.