Gavin Bazunu has made three competitive appearances for Pompey – and kept just as many clean sheets.
The latest shut-out arrived in a goalless draw with Doncaster that ensured his new side maintained their unbeaten start to the League One season.
He was kept busy before the break at the Keepmoat Stadium, making some key saves to deny Tommy Rowe and Ben Close.
But Bazunu felt that the Blues should have ultimately made the trip home with all three points in the bag.
The on-loan Manchester City stopper said: “I’m delighted with the clean sheet and we defended really well throughout.
“I felt we could have come away with all three points because we had chances that we should have taken.
"If we can keep this form going of conceding so few goals, then we give ourselves an excellent chance of winning games."
“We didn’t perform particularly well in the first half and had to make sure that we stayed in the game and reached half-time.
“I thought that we didn’t reach the levels that we know we’re capable of and got too deep as a back-line.
“We were able to talk about our tactics at the break and then got better, while their keeper made some good saves, so fair play to him.
“Like I said, we were under the cosh a bit earlier in the game, but saw that out and it’s now four clean sheets in the league which is a brilliant achievement.
“If we can keep this form going of conceding so few goals, then we give ourselves an excellent chance of winning games.”
Bazunu has impressed with his distribution since arriving on the south coast from the Premier League champions.
He said: “It’s just down to practice and repetition, staying out late after training and striking a lot of balls.”