Billy Davies' men were arguably the best team to arrive at Fratton Park so far this season and they were superior to Pompey in the first half due to their better pasing and movement.
Lewis McGugan forced the onrushing Jamie Ashdown into a superb block early on in the game, but he could only hit the side netting with his follow up effort.
Hayden Mullins then showed he had some skill by dancing past a few Forest players before firing his shot over the bar. Dave Kitson also had a great opportunity to score after Utaka did well to square the ball to him but his effort was deflected behind for a corner.
Pompey took the lead from that resulting corner as Ibrahima Sonko headed in Liam Lawrence's cross, injuring himself in the process. The lead would only last 10 minutes as Paul Anderson produced a powerful header of his own from McGugan's cross that Ashdown couldn't keep out.
McGugan should have put the visitors ahead as Pompey's defence was exposed by a pass from Chris Cohen but he completely miscued his shot and Pompey got away with it and went into the break with the scores level.
I don't know if Steve Cotterill has been secretly watching me play FIFA 11 but whenever I'm struggling in a match, I tend to move Nugent to left wing and play Utaka up front, which was exactly what the Pompey manager did in the second half and it seemed to work as the hosts upped the tempo.
Greg Halford's free kick sailed narrowly over whilst a great piece of football from the Pompey midfield led to Lawrence shooting just wide of the far post. Nugent also looked capable on the wing and twice tested Lee Camp with a curling effort and a lob that almost paid dividends.
The Pompey pressure did reap rewards eventually as Lawrence scored with a deflected shot to give the home side the lead again. That woke Forest up and on came Robert Earnshaw and Dele Adebola to turn the game in their favour.
The fresh faces galvanised the visitors and put Pompey on the back foot as the defence struggled to cope with the quick feet of Earnshaw and the movement of his team mates.
And Pompey fans must have feared the worst when ex-Scummer Dexter Blackstock arrived onto the scene as Forest were at their most dangerous. Ashdown saved an effort from him but not before Fratton Park breathed a huge sigh of relief after an unmarked Luke Chambers headed wide from a few yards out.
The game became extremely frustrating as it entered stoppage time as referee Mark Hayward awarded a couple of free kicks to Forest for seemingly nothing.
The frustration built as nobody in a blue shirt could take the initiative and fire the ball into an empty net as Camp had come up the pitch to try and force an equaliser, leaving his goal completely unguarded.
Thankfully, Pompey held out for a very well earned win that takes the club to 10th in the table, one point from the play-off places, three points from fourth place and eight points from the bottom three.
After a few wins where we have simply outscored the opposition in open games, it's good to see that Pompey know how to dig in and grind out a result.
More impressive was the performance of Ibrahima Sonko who I believe has turned his Pompey career around now. He was arguably our man of the match yesterday and probably at Hull too.
He is now showing us how good he is in the air and how capable he really is at defending. Sure, his distribution could be much better but all of a sudden Ricardo Rocha (and even Aaron Mokoena) are not certain of their places in the starting XI.
Credit must also go to Liam Lawrence (again) for providing the creative spark in the team. God help us if he gets injured or if we don't sign him permanently in January.
I'm still concerned about our defence as a unit though. Dickinson is good at blocking but his positional sense is absolutely woeful at times. Forest exploited our left hand side on many occasions yesterday and we were lucky that Forest's forays in that area didn't lead to a goal.
I'm also unconvinced that Aaron Mokoena, on his own merit, is anything more than an average centre back. He's good when Rocha is alongside him but without him he is prone to giving the ball away and lacks a dominant presence in the air too.
I shouldn't complain too much though, as Pompey are in incredible form that hasn't been experienced since our promotion winning season. Who knows? If we can keep this up then perhaps playing the Premier League next season isn't such an unrealistic ambition after all.
Pompey Player Ratings
Jamie Ashdown: 7 - A couple of very good saves.
Greg Halford: 6 - Solid home debut.
Ibrahima Sonko: 8 - Has turned things around.
Aaron Mokoena: 6 - Did OK but not entirely convincing without Rocha by his side.
Carl Dickinson: 5 - Caught out of position too many times.
Liam Lawrence: 8 - The difference maker going forward once again.
Hayden Mullins: 6 - Went about his business quitely.
Michael Brown: 6 - Not in the game as much as previous matches.
John Utaka: 7 - Supported the attack well.
David Nugent: 7 - Worked hard and may well have scored.
Dave Kitson: 5 - Didn't do much and was often hassled off the ball.
Ricardo Rocha (Utaka 89): N/A - Brought on to shore up the defence.
Hermann Hreidarsson (Kitson 90): N/A - Cameo appearance.