With Burnley virtually safe in the Premier League ahead of Sunday's home game against United there will be no upset from supporters about the Keane news breaking now, especially if it fires the starting gun on a bidding war for the player's services.
Scott Arfield remains a doubt with a hamstring injury but Johann Berg Gudmundsson is fit after a knee injury.
Rooney is only just returning from injury himself, but with Juan Mata also sidelined after groin surgery, Mourinho is prepared to risk Rooney even if he is undercooked.
Burnley host United at Turf Moor on Sunday and Dyche is backing Rooney to step up for the Swede.
In an ideal world Dyche would be able to keep his top players, but he sounded very realistic when discussing the matter and it doesn't appear to be too much of a problem for him at this stage with United ready to swoop for one of their former starlets.
However, if Burnley can remain resolute United could feel the fatigue created from Anderlecht taking them to extra-time on Thursday evening in a match that saw Marcos Rojo and top goalscorer Zlatan Ibrahimović come off injured.
Asked if he will make wholesale changes, Mourinho laughed and said: "No. Herrera plays, he didn't play today [Thursday], one yellow he would miss [the] semi-final".
Uber takes to the skies with next ride-hailing project
Uber said the project was to "enable customers in the future to push a button and get a high-speed flight in and around cities". You might recall Uber detailed its plans to create the world's first functional air taxi in a white paper back in October.
For Manchester United, this is a massive game for different reasons.
But Keane has often spoken of how much first-team football has helped him to develop and he will want to ensure he will be getting regular starts wherever he decides to move at the end of the season, with a fee in excess of £20m surely on the cards despite his contract situation.
Burnley have now won only once in 11 matches and are five points off the relegation zone in 15th.
One more draw would equal their club record of 13 in a Premier League season, set in 1998-99. José Mourinho's side have earned 30 points from 14 games on the road, winning nine and losing just two.
It is also believed that the Red Devils would be willing to waive part of their 25% sell-on clause to conclude a deal with the Clarets for the England worldwide.
Zlatan Ibrahimovic has scored in seven of his last eight league away appearances, with the exception coming in the 1-1 draw at Stoke on 21 January.
They are now holding fifth place in the Premier League with 57 points from 31 matches.