On a rain-lashed, weirdly subdued night at Molineux, in a game twice rearranged because of fixture confusion higher up football's foodchain, it looked for most of the 90 minutes that it would have been best off postponing it permanently.
In a first half of desperately poor quality, neither side managed a single shot on target between them, Pompey's Estonian midfielder Rocco Shein coming closest with a left-foot effort which arrowed just past the right post.
But, on 62 minutes, half-time substitute James finally found the breakthrough.
The free-scoring Wales midfielder's 25th career goal looked to have done enough to earn all three points. when he took a return pass from top scorer Fer Lopez to drill home a powerful right-foot finish - his second goal coming off the bench since his mid-August return to English football from French top flight outfit Rennes.
But Pompey kept plugging away - and, despite James' introduction having made a big difference to the hosts, it was the visitors who had the final word.
While Wolves do at last climb one place to seventh in a Midlands-heavy Championship play-off zone on 18 points from 11 games, they remain behind Blues (4th), Albion (5th) and Stoke City (6th), while Mousinho's Pompey remain 13th with 15 points.