Boro had clinched their first win in six Championship matches at Reading on Saturday and they made a fine start at Hull when Martin Braithwaite fired home after 13 minutes before Britt Assombalonga put Boro two goals to the good before half-time.
Substitute Kamil Grosicki pulled one back with a nice finish in the 72nd minute, but Grant Leadbitter’s late penalty, after Ashley Fletcher had been fouled by Michael Hector, killed off any hopes the Tigers had of a comeback.
To compound a miserable evening Hector was sent off just before Leadbitter’s goal as Hull slipped to back-to-back defeats, having been beaten by Nottingham Forest at the weekend.
While Hull made three changes to their line-up Boro kept the same side that defeated the Royals but were forced into an 11th-minute substitution when Fabio limped off to be replaced by George Friend.
Fabio had moments earlier made a last-gasp intervention to stop Fraizer Campbell pouncing on a rebound after goalkeeper Darren Randolph had spilled a tame Jackson Irvine effort.
Almost immediately afterwards Hull midfielder Michael Stewart failed to control a loose ball on the edge of his area and was swiftly dispossessed by an opportunistic Braithwaite, who drilled low across Allan McGregor and into the net.
Hull responded with plenty of endeavour but were unimaginative and passive in the final third, while they were fortunate when Hector sliced an attempted clearance just wide of a post.
Boro, though, were in clinical mood and doubled their lead in the 36th minute when Cyrus Christie’s right-wing cross to the back post was headed across goal by Assombalonga for his eighth goal of the season to the delight of the notable visiting contingent.
Hull were booed off at half-time and manager Leonid Slutsky responded by bringing on Nouha Dicko on the resumption and Gosicki shortly afterwards, with Stewart and Seb Larsson making way.
Dicko should have halved the deficit on the hour mark when he was given a clear sight at goal but shot straight at Randolph, while only some last-ditch defending prevented Boro from further extending their lead on the next attack.
Ben Gibson’s header forced a fine save from McGregor but, as the game was becoming more stretched, Hull threatened a fightback.
They duly got back into the game in style through Grosicki’s sublime half-volley on the edge of the area after 72 minutes. But a comeback was dashed when Leadbitter scored from the spot five minutes from time after Middlesbrough substitute Fletcher had been upended from behind by last-man Hector.
The Hull centre-half was initially booked for the challenge, but referee Tim Robinson produced a red card for the unlucky defender after conferring with his assistant before Leadbitter coolly fired his penalty into the top corner.
📈 BOROFORM RATINGS MOTM
Stewart Downing 74%