Manchester City is a team that punishes any kind of mistake in your own half of the pitch and with Moreno returning from a semi-lengthy injury spell, it might not be wise to thrust him into the limelight just yet.
City come into the game still unbeaten in the league this season, and heavily linked with a move for Arsenal's Alexis Sanchez.
One of their biggest obstacles to doing so comes on Sunday, as they travel to Anfield to take on Liverpool.More news: Mud, Debris Block Highway 101 Days After Storm
Liverpool, meanwhile, find themselves on a run of four straight wins in all competitions, shooting down Swansea City, Leicester City and Burnley in the league before pipping Everton in the FA Cup third round last weekend.
Meanwhile, Mourinho is now preparing his team for their Premier League clash against Stoke City at Old Trafford on Monday night.
That task will have become a lot harder after wantaway Philippe Coutinho finally forced through his move to Barcelona.More news: Archer Daniels Midland (NYSE:ADM) Getting Somewhat Favorable News Coverage, Report Shows
Liverpool are 18 points below Manchester City and are looking to finish second in the league as there is very little chance of catching Guardiola's side given their rampant form since August.
Back in September, the Reds were ripped apart by the Citizens 5-0 at the Etihad Stadium but at Anfield, Klopp's men will hold stronger cards so it will be an intriguing battle.
How Jurgen Klopp spends the £142 million could make or break Liverpool's season - and given previous January transfer dealings, Reds supporters will hope any arrivals are more Luis Suarez than Andy Carroll.More news: The Walking Dead renewed for season 9 with a new showrunner
The player has impressed in Ukraine under Paulo Fonseca and also impressed when the side faced City in the Champions League.