After the defeat to Boro, Hull conceded 34 goals in 19 games, the second worst defensive record in the league.
Since then, they have conceded just nine goals in 12 games, winning eight and keeping six clean sheets.
By the end of January, they had won more points and games, scored more goals and kept more clean sheets than in the entire 2024-25 season.
The Tigers are averaging 45% possession, compared to 49% last season, and are completing an average of 276 passes per game, 70 fewer than last season.
Last season, under Tim Walter and Sells, the team scored two goals off fast breaks as defined by soccer statistician Opta, but this season they have already scored nine goals.
Experienced striker Oli McBurnie, who has scored 12 goals in 22 league appearances this season, said the team has benefited from the confidence the manager and staff have in their players.
“It wasn’t like a dictatorship. They came in and understood what English football and culture is about,” he told BBC Radio Humberside.
“They will talk to you and of course the manager has the final say, but they were fantastic.
“They understand the league, they know we know the league, they understand that our opinions matter, and Dean’s presence is [Holden] The number of staff is huge for them. ”