United are just one step away from Wembley
Mata and Fellaini do the damage in the first leg
Marouane Fellaini repaid Jose Mourinho's faith with a late header that gave Manchester United a 2-0 EFL Cup semi-final advantage against injury-ravaged Hull.
The Belgium midfielder has long been a divisive figure at Old Trafford and has even been jeered by pockets of home fans recently.
However, Fellaini has been continually backed by Mourinho and ended last night's first-leg encounter with the Stretford End chanting his name after he nodded home a late goal to add to Juan Mata's close-range opener.
It was a late sucker-punch for a Hull side forced to play two midfielders in defence due to injury problems that worsened as Markus Henriksen and Josh Tymon were forced off in the club's first EFL Cup semi-final appearance.
Hull, bottom of the Premier League, equipped themselves well for the most part and it looked like Marco Silva's men would restrict United to Mata's 56th-minute goal, which came shortly after Wayne Rooney had passed up a fine chance to notch a record 250th goal for the club.
Paul Pogba hit the post as the Tigers dug deep, before substitute Fellaini rose at the far post to send in a looping header.
The midfielder went over to hug Mourinho after a goal that wrapped up a ninth successive win in all competitions for in-form United.
This was a game dominated by United, and the big guns of their midfield in particular, Paul Pogba and Henrikh Mkhitaryan, but they struggled to unlock the away team with a five-man midfield and a determined application to their task.
Only 1,400 of the 9,000 tickets available to the away team's fans were taken at Old Trafford and one can understand their disaffection at much of the season.
Mourinho had left his place in the technical area a few minutes before the end of the first half and disappeared down the tunnel, the kind of gesture that is always intended to mean something - but what?
His team had dominated the first half and even so their best chances had been of the kind that Hull could live with.
At the other end there was just one chance for Hull and a good one too when Adama Diomande headed a cross against David De Gea's post. The flag went up subsequently but the Hull striker was not offside.
There was an early injury to Henriksen who went off with his right arm in a sling after just 19 minutes with what looked like a shoulder or collarbone injury after he bounced off Pogba and landed awkwardly.
There was no Zlatan Ibrahimovic in the side for United, absent through illness for the first time this season other than the one game he served as a suspension.
The best chance of the night for Rooney to reach the promised land of 250 career goals for United came six minutes into the second half but his unleashed shot was just beyond Eldin Jakupovic's far post.
The striker was replaced with Anthony Martial just before the hour, but Mata had given United the lead before that. The second came when Martial won the ball on the left and Matteo Darmian picked out Fellaini at the back post for a header past Jakupovic to give United a win that puts them within sight of the final.