If Chelsea regain the title at the end of this season – something which, even at this early stage, looks a distinct possibility – they will surely owe a debt of particular gratitude to the midfielder whose goals secure so many crucial points.
Frank Lampard may have had a mixed reaction from the Wembley crowed upon being introduced before last week's England game, but his place in the folklore of Stamford Bridge is secure thanks to a long sequence of performances such as the one he produced on Saturday, when, once again, one of his powerful drives from the edge of the penalty area made all the difference.
The jeers he suffered before scoring England's goal against Germany on Wednesday provoked disbelief in both the Chelsea manager, Jose Mourinho, and his Portsmouth counterpart, Harry Redknapp.
The latter, of course, just happens to be a former manager of Lampard's at West Ham, and indeed his uncle. But there was more than mere nepotism in his appraisal of the nephew whose moment of enterprise in the 31st minute, when he seized on a knockdown from Didier Drogba and drove a low shot under the fallible figure of David James, decided this keenly fought contest.
Redknapp recalled the occasion when he had looked down from his office at the West Ham training ground on an afternoon of driving rain and saw a young player working tirelessly on sprints and turns: Frank Lampard Jnr.
"His dad did exactly the same," said Redknapp, who played with Lampard Snr for West Ham in the late 1960s and early 1970s. "He made himself into a fantastic footballer. And as his dad used to say to him, 'If you practise hard enough, you get lucky'.
"So yeah, I was surprised by what happened at Wembley. Because let's be honest, he's a fantastic role model. He's a good lad. A proper geezer."
You can't say fairer than that, although Mourinho, with characteristic eloquence, tried. "If he has critics, I am not one of them," he said. "If he has people who support him every time, I'm one of them. He's strong, mentally ready and he wants to play a great season. He's a winner so he was not happy with only winning two cups last season."
Lampard may still need to show he can fit into an England midfield with Steven Gerrard, and – despite his smartly taken effort against Germany – he has yet to convert his goalscoring knack to the international setting. But for matches such as Chelsea faced on Saturday – wearied by midweek international duties, slowed by a sun that scorched with continental intensity and facing opposition who combined industry and organisation with unpredictable bursts of improvisation – Lampard is exactly what is required.
It has to be said, however, that his decisive flourish was aided and abetted by a less than convincing reaction from the man who now appears to stand as England's No 1 keeper following the erratic performance from Paul Robinson.
James, whose own lapses of concentration have been largely banished since his move to Portsmouth last year, once admitted that his preparations for a game had been adversely affected by spending too long on a computer game the previous night.
Before this match, according to Redknapp, he spent hours watching videos in the team hotel. But they were of Chelsea, and of his own previous performances. No one could question James' dedication or honesty, but as he dived to his left in an attempt to block a shot which he later claimed had taken a deflection off Portsmouth full-back Hermann Hreidarsson's boot, the ball sneaked in between his extended arm and his body. It was like watching a dropped catch on the boundary – not great viewing for the onlooking England manager, Steve McClaren, and his deputy, Terry Venables.
Chelsea, meanwhile, have their own gaze fixed upon the prize they ceded to Manchester United last season, and victories like this, earned despite a muted performance, will only strengthen their resolve.
On the other hand, Portsmouth, with the dreadnought Sol Campbell at the back and the ageless, awkward Nwankwo Kanu up front, look capable of another top-half finish.
The latter provoked Redknapp to memorable heights of rhetoric in the aftermath: "He's tall. He's skinny. He's what he is, isn't he? He's a footballer." Spot on, Harry...Reuse content