Josh Windass’ 11th minute strike settled matters in a game of few opportunities, while Dominic Iorfa was sent off for the visitors in the second half.
It maintains the Owls’ lead at the top of League One, yet there were still a number of encouraging Blues displays – and here are our on-the-whistle player ratings...
9. Conor Chaplin - 7
Always so positive on the ball and such a progressive player, which is a vital outlet for the Blues. Still nowhere near to scoring, though, and elected to pass rather than shoot with one second-half effort. Goal continues to elude. Photo: Graham Hunt
10. Adrian Segecic - 7
Just before half-time he took a heavy touch from Alli’s excellent pass and wasted a shooting chance. But when the two combined again after the break, it led to Pompey’s opener. Lovely first-time left-footed finish too, yet was a really quiet game for the Australian. Photo: Graham Hunt
11. Millenic Alli - 8 - MOM
(Replaced by Jordan Williams on 73 mins) - Straight in for his Pompey debut on the left wing and instantly impressed with his directness and willingness to get at defenders. Produced one driving run which ended in an excellent pass to put Segecic clean through, but the Australian’s touch was heavy and the chance went. Then another great run, this time in the second half, was finished by Segecic for Pompey’s opener. Unpredictable but exciting. Photo: Portsmouth FC
12. Colby Bishop - 7
Built on his Arsenal showing by leading the line well, holding the ball up and causing problems. Really made his presence felt and another encouraging showing. Photo: Graham Hunt