Wayne Rooney is fighting to save his job at Plymouth Argyle, with the manager under heightened scrutiny after a hugely damaging week of results.

Plymouth were hammered 4-0 at Bristol City on Saturday, four days on from a humiliating 6-1 defeat at Norwich. The former England and Manchester United captain is not thought to be at immediate risk of losing his job but defeat at home to Oxford next Saturday will further jeopardise his position.

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The Plymouth chairman, Simon Hallett, was in the away end at Ashton Gate on Saturday to witness a second-half capitulation, which Rooney acknowledged was a “big embarrassment”. It was not the first collapse under Rooney, whose side lost 4-0 at Sheffield Wednesday on the opening day of the season and were thrashed 5-0 at fellow strugglers Cardiff in October.

After Plymouth’s loss at Norwich on Tuesday, Rooney, alluding to an alarming run without an away win all season, said: “We have got to get to the bottom of why it keeps happening – it can’t carry on like this. We were nowhere near good enough – we are down to the bare bones with injuries but that is no excuse.”

Plymouth are 21st in the Championship, a place and two points above the relegation zone after a run of one win in nine matches. The former England captain has won four league games in charge but only once since 5 October, last month’s victory at home to bottom-placed Portsmouth.

Rooney, meanwhile, is the subject of a behind-the-scenes documentary following his progress at Plymouth, which was approved after internal discussions. The 39-year-old insisted the filming, which began last month, is not a distraction. “It has to be at the right times and anything which we feel could affect players on a match day, the access won’t be there,” he said.

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“It happens nowadays anyway at most football clubs – they have their own internal cameras almost everywhere, so I don’t think it’s any different for the players or a shock for the players to have cameras around. Once they get used to it, it’s not an issue.”

This is Rooney’s first role since being sacked by Birmingham in January, after 83 days. His appointment was driven by Plymouth’s director of football, Neil Dewsnip, who coached Rooney as a youngster at Everton.

Rooney’s wife, Coleen, is in the jungle in Australia, where she is among the favourites to win I’m A Celebrity … Get Me Out Of Here! Coleen revealed on the show how their Cheshire mansion home includes a full-size football pitch.