Scott Malone levelled for the Lions on 21 minutes, before George Saville put the home side in front just before the half-hour mark.
Pompey’s hopes of a second-half comeback were thwarted after Callum Johnson was shown a straight red card three minutes after the break.
1. Alex Bass - 7
Some very good stops, although nervy moments at the end with a few mis-hit clearances. Photo: JPIMedia
2. Callum Johnson - 6
Debatable sending off soured a decent return to the side for the right-back. Photo: JPIMedia
3. Sean Raggett - 8
Has started the season off superbly and producing another towering display. Photo: JPIMedia
4. Clark Robertson - 7
Strong alongside Raggett with the pair developing a good understanding. Photo: JPIMedia
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