It was a win that saw Pompey move to within three points of the League One play-off places.
And John Mousinho was delighted with the outcome of a Fratton contest with Forest Green, even if he admitted the performance was not perfect.
The hosts had to remain patient to break down their stubborn opponents, with Owen Dale heading home the crucial goal from a Joe Rafferty delivery shortly after the interval.
Mousinho wanted to see more ambition from his side after that point, although was certainly satisfied with the victory.
The Blues boss said: “We got the goal and perhaps sat off a bit, while the shackles were off for Forest Green and they then started to play.
“I don’t think we coped with that particularly well and we didn’t put the game to bed by taking the chances we created.
“But, overall, three points is the most important thing and I thought we controlled the tempo throughout the first half.
“Ultimately, we got the goal from that quality cross and we’re obviously happy to come away with the win and clean sheet.
"We knew that we’d be three points behind Bolton if we won and considering the gap between the sides in January, it’s a good position to be in."
“Forest Green are very well organised and it’s very tough to break down – we saw that last week when they managed to beat one of the best sides in the division.
“So we knew we’d have to work hard and move the ball quickly, but they’re difficult games to play in and you’ve got to keep hunting for those opportunities.
“I can’t remember them having many clear-cut chances, but if something deflects off someone and loops in then you say we got what we deserved because we hadn’t got that second or third goal.
“We knew that we’d be three points behind Bolton if we won and considering the gap between the sides in January, it’s a good position to be in.
“There are seven games to go and we’ll have to play a bit better to keep pushing on, but we’re still alive.”
There were concerns when skipper Clark Robertson trudged off the pitch in the second half, having only recently retuned from a long lay-off.
Mousinho said: “He cramped up from the calf to the hamstring, but it’s not a big issue – it’s unsurprising considering the time he’s been out.
“Reeco Hackett was missing through injury after getting a knock on the knee that just tightened up during the week. It’s a shame for him, although nothing too serious.”