The former Queens Park Rangers striker came off the bench to score the winner at the KC Stadium after Steve Bruce's side had came from 2-0 down to draw level before half-time
Chelsea raced into a two-goal lead at the KC Stadium on Sunday courtesy of classy finishes from Eden Hazard and Diego Costa inside nine minutes.
|VIEW FROM KC STADIUM
|By Peter Staunton
It's not very Chelsea to drop two-goal leads and it's even more rare that they drop points from winning positions like they enjoyed early on at the KC Stadium.
Eden Hazard and Diego Costa provided the fillip of two early goals and from there we usually know how a game involving a Mourinho team plays out.
However, there were uncharacteristic lapses shown at the back as Ahmed Elmohamady and then Abel Hernandez turned 2-0 into 2-2.
Nevertheless, Chelsea had enough in the tank, barely, to get over the line. Mourinho has been criticised for working too often with the same core of players from 2013-14 but it was very much a reserve in the shape of Loic Remy who delivered the points.
As winners go, it was untidy but enough and Manchester City will not get many more chances to overhaul what is now a six point and one match advantage.
A stunning triple save from Courtois went someway to repaying his team-mates as the hosts continued to press forward.
But Remy had the final say with his first touch after replacing Costa, and it was a moment to forget for Allan McGregor, as the striker's tame shot squirmed through his legs and into the net.
Victory for the Blues ensured they head into the international break in command of the title race - they still have a game in hand over second-placed Manchester City - while Hull remain just three points above the relegation zone.
Hazard scored a stunning goal at Hull last season and he took less than two minutes to hit another sublime effort, latching onto Costa's lay-off and surging forward before letting fly with his left foot to find the far corner from 20 yards.
Hernandez was wasteful when one-on-one soon after, and Hull were punished in the ninth minute as Cesc Fabregas picked out Costa and the Spain striker cut in from the left before finishing inside the far post in measured style.
Hull retained a threat going forward, though, and they stunned Chelsea by scoring twice in little more than a minute to draw level.
Elmohamady gave Steve Bruce's men hope when he arrived at the back post to convert Andy Robertson's teasing cross after the left-back beat Ivanovic after 26 minutes.
And Hull fans had barely finished celebrating when Courtois inexplicably lost control of the ball to gift the grateful Hernandez a tap-in.
Perhaps with harsh words from Mourinho ringing in their ears, Chelsea made a bright start to the second half, with Fabregas shooting just wide following a slick move.
Courtois then redeemed himself by denying Elmohamady, Jake Livermore and Gaston Ramirez in quick succession, as Chelsea continued to look vulnerable at the back.
Costa, who moved level on 19 goals with Harry Kane in the race for the Premier League golden boot, was withdrawn clutching his hamstring 15 minutes from time but his replacement Remy earned his side all three points almost immediately.
Willian crossed for the former QPR man, whose left-footed effort should have been dealt with by McGregor but the Hull keeper allowed the ball to creep past him, keeping Bruce's side firmly in the battle at the bottom and tightening Chelsea's grip on top spot.