Smallwood gave Hull a fourth-minute lead before a thumping finish from Longman doubled the advantage.

Ian Maatsen thought he had pulled one back late on, but officials did not receive confirmation that the ball had crossed the line.

His half-volley was partially cleared off the line by Jacob Greaves and cannoned into goalkeeper Matt Ingram and seemingly over the line, but goalline technology did not send its signal to referee John Busby.

It would have given Coventry the chance to press for a point in the final stages, but defeat undermined their hopes of seriously threatening the top six.

Hull's first win in three matches eased any lingering relegation worries as they moved 13 points clear of the bottom three with eight games remaining.

Under-23s head coach Luke Tisdale took charge of the hosts after goalkeeping coach Dennis Lawrence and first-team coach Aled Williams received positive Covid tests on Monday, and manager Mark Robins remained in isolation.

A smart move down the right saw the Tigers take an early lead as Longman freed George Honeyman who squared for Smallwood to fire low and almost straight through goalkeeper Simon Moore.

But there was no chance for Moore with Hull's second as Smallwood's corner found Longman on the edge of the area, who took one touch and fired a shot in off the bar.

Coventry stand-in coach Luke Tisdale told BBC Coventry and Warwickshire:

"Probably everyone knows it wasn't the performance level we've seen so far this season.

"I don't know if the goal was over the line but it would have given us a lift with the amount of late goals we score, but you have to trust the technology.

"We obviously didn't start very well and they defended well and stopped us doing what we normally do."

Hull City manager Shota Arveladze told BBC Radio Tees:

"I am really happy to see the performance, creating chances, scoring goals and also defending as a team.

"It may be the best performance I have seen. We knew Coventry play between the lines and that makes it difficult to defend.

"If we show more of this we don't have to count the points."