Lampard arrived a tidy, chubby plodder and quickly elevated himself to the top table of the world's box-to-box operators, and Chelsea's highest-ever scorer with 211 goals.
He readily admits that he had to work at it more than others at the start of his career. He laughs now as he tells the story of a young Lampard who, embarrassed, would sneak off after training for dedicated sprint sessions on his own.
That sprint would later underpin his hallmark: With the ball wide, the overlapping full-back bursting to the byline, Lampard would arrive on the scene via a perfectly timed under-the-radar charge and smash at goal.
A commentator's cry of "typical Lampard" meant an expertly taken finish, and few other modern midfield players have had that relationship with goalscoring.
He played at least 35 league games in every season bar one from 2001-02 to 2009-10 and produced a unique run of 10 campaigns scoring at least 10 goals from midfield, starting around the time Mourinho arrived in 2004.
"I'd never had a manager who, while I'm standing in the shower, tells me I'm the best player in the world," Lampard had said. "He did that. I’ll never forget it."
It is difficult to ascertain a peak in such consistent level of high performance, but two seasons stand out.
Statistically at least, his 2010 season under Carlo Ancelotti was his most impressive, when Chelsea won back the title for the first time since Mourinho. Lampard scored 22 goals in 36 league games and netted in the quarter-finals and semi-finals on the way to winning the FA Cup.
But in truth his best may have come much earlier. In 2004-05, Mourinho's first year, Lampard scooped the Premier League and writers' player of the year awards—he scored both goals in the 2-0 win at Bolton that secured the club the title for the first time in 50 years—and it is often forgotten that he was Ballon d'Or runner-up, behind Ronaldinho. Steven Gerrard, incidentally, came third.
The great debates of where Lampard fits within the echelons of Premier League greats and modern English midfielders will never be agreed upon but if, as they say, scoring goals is the hardest part of football, then his place near the very top of both lists should never be questioned.
The latter argument often brings a comparison with Gerrard and Paul Scholes. It is an almost answerless question taken on by Gary Neville and Jamie Carragher not so long ago, where the pundits' allegiances unsurprisingly left Lampard with no backer.
But he is rightly on a plane with the very best England midfield players, and not just for his sheer quantity of goals but because, like Gerrard, he would deliver on the big occasion.
Lampard talks with incredible fondness of his goals at Bolton, but there were many other crucial moments. His goal in the Nou Camp in 2006, tight against the byline when a show of his unheralded quick feet and floated chip beat Victor Valdes from a ridiculous angle.
His winning strike against Everton in the 2009 Everton FA Cup final was a fine example of shooting from range and his reliable left foot.
There was the pressure penalty he scored against Liverpool the week after his mother died to propel Chelsea to the Champions League final in Moscow in 2008, and the crucial equalising goal in the final itself moments before half-time that transformed the match and brought Chelsea so close to victory.
His brilliant extra-time swivel and jab which hit the crossbar just need a shade of luck to have made it "that Lampard final" (a similar bit of luck to that needed in Bloemfontein two years later).
A personal favourite was in Chelsea's incredible beating of Barcelona in the 2012 Champions League semi-final. It was 0-0 at Stamford Bridge when Lampard dispossessed Lionel Messi near the halfway line before surveying the landscape and chopping an exquisite reverse ball that only he had seen.
It hung obediently in the direct line of Ramires’'sprint forward, at chest height. He took it in his stride and seconds later Dider Drogba had scored. It was the first piece in that most unfathomable of victories.
In the cauldron of the Nou Camp six days later, with Chelsea down a goal—and a man—Lampard shrugged off the attentions of Javier Mascherano and slipped another beautifully weighted pass into the path of the on-rushing Ramires, who chipped Valdes quite arrogantly to render the grand old stadium silent.
A Neville goalgasm later and the most incredible win in the club's history was complete, with Lampard at it's heart.
Has he had the recognition he deserves? One imagines the adoration of Chelsea fans is enough for Lampard, but in truth he was a model professional whom all could enjoy. He never won without grace or lost without class.
Through the radical changes that Chelsea Football Club has endured in his stay, Lampard has not shaken from his position as one of the team's most important players, week after week and season after season.
That in itself is a fine accomplishment. Perhaps a heroic moment in a grandstand England game has been missing (though the same could be said of every top England player since Owen's goal against Argentina in '98). It may yet come, of course.
Maybe he lacks that element of technical giftedness that marks out many of the world's top midfielders today. Andres Iniesta springs to mind, in essence another attack-minded midfield player and yet in practice a total contrast to Lampard's style and skillset.
But for all the qualities of the quick-footed creator, Iniesta has just 33 goals in 337 La Liga games for Barca. In 429 league appearances, Lampard scored 147 times.
Lampard did have supreme technique: in his finishing. The left-arm high, toe pointed at the floor, laces flashing through the centre of the ball and always a deliberately extended right leg following through in the direction he arrowed.
This was not a gift but something he practised and has never stopped practising. Gerrard has an ingrained athleticism and Scholes had a supremely natural technical ability: He picked up a violin and could play a concerto.
But Lampard was self-taught. Note by note, chord by chord, until he could play, wonderfully so.
Quite simply, he is the best goalscoring midfielder the Premier League has known, and for that self-cultivated knack he will be remembered more than anything.
Back then, 13 years ago, a midfield player would "arrive in the box like Scholes." Today, they get there like Lampard.