Bristol City manager Keith Millen admitted his patience had run out after seeing his side lose 2-0 at home to Watford.
Marvin Sordell notched his third goal in two games for Watford inside the opening two minutes when he slammed home a loose ball and David Graham's deflected strike in the opening exchanges of the second period ensured the Hornets breezed past a lacklustre City at Ashton Gate.
Millen said: "I didn't want to change the team after a good performance at Scunthorpe on Saturday, but now I will be looking at both personnel and shape," he said.
"We gifted the opposition the points. Our defenders are not doing their job on the people they are marking and there were definite similarities to our first two home games.
"I'm not too downhearted because I know we have the players in our squad to improve and move up the table.
"We have a reserve game where I'll be looking at several players and I won't be afraid to make the necessary changes."