October 7, 2020 | 2:23pm

Bill O’Brien’s poor decision-making probably cost him his job in the end, but his relationship with players, most notably J.J. Watt, couldn’t have helped, either.

The Texans fired their coach/general manager on Monday, and on Wednesday reports surfaced of friction between O’Brien and Watt.

The Houston Chronicle reported the two had an argument on the practice field and O’Brien also got into it with defensive coordinator Anthony Weaver. There were even “verbal altercations” between other staff members in the final weeks of O’Brien’s tenure with the Texans. ESPN 97.5 FM in Houston reported that Watt called out O’Brien for his coaching ability and it started a player revolt against him.

Watt posted a cryptic tweet on Tuesday of the NRG Stadium roof being open and the sun shining through.

Bill O'Brien and J.J. Watt
Bill O’Brien and J.J. WattAP

O’Brien began to feel heat in the offseason, when he dealt away star receiver DeAndre Hopkins to the Cardinals for fading running back David Johnson and two draft picks. And with the team off to an 0-4 start with the league’s largest payroll and no first- or second-round draft picks in the 2021 NFL Draft, he was let go.