Pompey striker who Harry Redknapp splashed out £6m to land from Preston in 2007.
Nugent struggled to make an impression while Redknapp was at he club and fell out of favour. He was eventually loaned out to Burnley in 2009.
The popular Scouser has been invigorated under Steve Cotterill, however, and become a key part of the Blues set-up this campaign.
Goals have steadily flowed for the former Bury forward this season.
Nugent picked up a single England cap in 2007 - and scored in the 3-0 win over Andorra.
Former clubs: Bury, Preston, Burnley (loan)
Date of birth: 2/5/85
Height: 5ft 9in