The South Coast side duly subsided to their seventh successive away defeat in the Premiership without giving Shay Given a shot to save all afternoon, even after Harry Redknapp tried to shake things up with two half-time substitutions. Having brought in almost a full team of newcomers during the transfer window, Redknapp must wonder where to turn next.
For Newcastle, four successive home games after the visit to Villa Park next Saturday offer an excellent chance to climb further away from the bottom six and reach the FA Cup quarter-final. To the good fortune of Glenn Roeder, the caretaker who genuinely does not want to be a permanent manager, injuries are easing too, Kieron Dyer's return as a second-half substitute being greeted almost as rapturously as the goal just after the hour with which Alan Shearer finally broke Jackie Milburn's long-standing club record.
It was only his fifth in 24 Premiership games this season, which goes some way towards explaining the team's struggles, but his 201st in 394 appearances since Kevin Keegan brought him home 10 years ago. The straightforward clip past Dean Kiely, Portsmouth's busiest player, also had the effect of securing, even at that early stage, a first victory since the middle of December, when Michael Owen scored a hat-trick at West Ham.
How Souness must curse the injury that deprived him of Owen shortly after, not to mention the midweek fixture at Manchester City last Wednesday, when he might have enjoyed the run of fixtures Roeder has inherited. "I only wish Graeme had been here to see it," Shearer said of his magical moment. "He is a decent, honest hard-working man, not a bitter one, and would have wanted us to win today."
Managers come and go but little else changes at St James'; certainly not the delusions of grandeur. Here was the chairman Freddy Shepherd, talking about "one of the biggest jobs in world football", and Mick Quinn, the former striker turned racing trainer and local radio pundit, rating the job as bigger than the one being vacated by Sven Goran Eriksson this summer.
The sense of (bad) timing remains too, Souness being evicted less than 48 hours after the transfer window closed, just as Kenny Dalglish, Ruud Gullit and Sir Bobby Robson all went at the end of August, having spent the summer transfer budget.
So Roeder, assisted by Terry McDermott (who had survived the midweek cull), was left to make do with what he had. He decided to leave the defence as it was, probably for want of much alternative, and was rewarded with a rare clean sheet.
Two changes in other areas, both to good effect, brought Nolberto Solano in for Lee Clark in midfield and restored Shola Ameobi to the attack in place of Michael Chopra. Albert Luque, one of Souness's most extravagant signings, was nowhere to be seen, having gone straight home - with Roeder's blessing - once he was omitted from the 16. Ameobi's coltish enthusiasm ensured he was not missed.
Of Redknapp's nine (repeat, nine) January signings, six were to be found in the starting XI. It was not surprising that lack of familiarity in the Portsmouth ranks occasionally bred the sort of confusion that has blighted Newcastle's defence for most of the season. They were redundant as an attacking force and forced only two even slightly uncomfortable moments, both after Given had rushed from his goal and not claimed the ball.
Roeder was justified in claiming: "We let them off the hook at half-time with 1-0." His side made seven decent first-half chances, Kiely distinguishing himself with good saves. His double-block from Shearer and Ameobi was the pick, and luck was against him as Newcastle finally scored in the 41st minute. Kiely did well to parry Shearer's header from a cross by Solano, but Charles N'Zogbia was well placed to drive in the rebound.
There were brief signs of improvement from Portsmouth after Redknapp removed Andy Griffin and Wayne Routledge at the interval. He saw Matthew Taylor's dangerous low cross elude Benjani Mwaruwari, and Titus Bramble twice rescue Given's impetuosity. Those half-chances were soon forgotten, subsumed by the Shearer moment. In the 64th minute, both he and Ameobi managed for once to avoid running offside and after latching on to the latter's flick, Shearer was legitimately in the clear to beat Kiely and claim his record at last.
The celebrations were prolonged, but Portsmouth might not have been thrilled to see the referee Mark Halsey add to them with a handshake when a word or two would have sufficed. "I'm proud to have been part of a special day," said Roeder, whose lack of a coaching licence means that under Premier League rules he cannot continue in charge beyond the end of April.
Perhaps Shepherd will appoint himself manager for the final game on 7 May to pit his wits against the young upstart Mourinho. Redknapp gets to do so shortly. "Our next two games are nice and easy," he said, resorting to the humour of the relegation gallows: "Manchester United and Chelsea."