Chelsea are currently six points clear at the top of the Premier League table, with Manchester City second, followed by Arsenal, Manchester United and Liverpool.
United take on Liverpool at Anfield on Sunday afternoon as the Red Devils look to keep their place in the top four of the Premier League.
Chelsea, meanwhile, travel to Hull City aiming for a victory to take a step closer to winning their first top-flight title since 2010 and remain the overwhelming favourites to lift the trophy.
And Blues boss Mourinho believes that there are still five teams left in the race for the title.
Speaking at a news conference at Chelsea’s Cobham training ground on Friday afternoon, Mourinho said: “There are still five teams in it because the distance is still mathematically possible.
“The teams in fourth and fifth don’t have to fight one, but three teams, so normally I would say it’s between the first three. But the distance is short, I look at them and maths says things are open.”
Arsenal travel to Newcastle United on Saturday, while defending champions Manchester City host West Bromwich Albion.
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