A left-field appointment at the time, but crucially the right one by Rich Hughes and Andy Cullen, the head coach guided the Blues back to the Championship after a 12-year hiatus. His side stormed to the League One title in his first full campaign in management and were victorious in 28 of their 46 league games, where they achieved 97 points.
Despite a difficult start back in the second-tier having picked up just one win in their opening 14 fixtures, Pompey now sit 17th and four points above the relegation zone ahead of a vital eight-game run-in as they bid to maintain their second-tier status.
Mousinho is now the second-longest serving manager in the division, which speaks volumes of the impressive job he’s done after succeeding Danny Cowley in January 2023.
But how does the head coach’s win percentage compare to his predecessors in the Fratton Park hot seat?
We’ve taken a look at every boss who has taken charge of Pompey in the 21st century to determine where Mousinho’s current figures rank.
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1. How John Mousinho's numbers compare
How John Mousinho's Pompey win percentage compares to Fratton Park greats. Pic: Jason Brown/ProSportsImages | Jason Brown/ProSportsImages

2. Tony Adams - 18.18%
October 2008 - February 2009. PICTURE: STEVE REID (084754-284) | STEVE REID Photo: Steve Reid


4. Richie Barker - 20%
December 2013 - March 2014. Picture: Pete Norton/Getty Images | Getty Images