Diego Costa a reminder of players Jose Mourinho has seen success with at Chelsea before

Diego Costa is a cross between the two defining players of Jose Mourinho’s first spell at Chelsea: the finisher supreme Frank Lampard and the warrior-striker Didier Drogba.

Diego Costa of Chelsea celebrates scoring his team's sixth goal during their English Premier League match at Everton on August 30, 2014 in Liverpool, England. Chelsea won 6-3. Laurence Griffiths / GShow more

It was entirely fitting that Jose Mourinho's first English Premier League title was clinched by a 2-0 win.

It seemed the perfect Mourinho scoreline, with the lead and the insurance of an extra goal in the unlikely event that the opposition scored, but without any superfluous strikes.

That 2-0 triumph at Bolton Wanderers in 2005 was clinched by a brace from Frank Lampard, the quintessential Mourinho player. He was relentless in his efficiency.

The Portuguese did not enjoy Chelsea's 6-3 win at Everton. To be more specific, he did not enjoy their defending. They had the 2-0 lead he cherishes after three minutes and did not seal victory for a further 87. His team were uncharacteristically careless, or some of them were.

In attack, he had a player who belongs in the truest traditions of Mourinho footballers.

Diego Costa struck twice, bookending a madcap game with displays of cold-blooded calmness in front of goal. Three games into his Chelsea career, he has scored four times. Each of his first three shots on target nestled in the net. That is efficiency.

Costa is a cross between the two defining players of Mourinho's first spell at Chelsea: the finisher supreme Lampard and the warrior-striker Didier Drogba.

Costa went into battle with the Everton defence, equipped with a clinical touch, a purposeful style of running and an elementary grasp of English that still proved sufficient to wind them up.

Along the way, it brought a comparison with Chelsea’s last trip to Everton. Mourinho did not enjoy that much either, but for very different reasons.

Chelsea lost 1-0 and their manager was left bemoaning their lack of predatory instinct.

While Samuel Eto’o scored on his Everton debut against Chelsea on Saturday – one of the goals that Mourinho deemed eminently avoidable – he failed to find the net on his bow for the Londoners in the equivalent fixture 11 months ago.

Afterwards Mourinho, with an interesting use of the past tense, said: “Samuel was a killer all his career.”

Costa is a killer. Not literally, despite his rows with the Everton rearguard, but in his ruthlessness.

That merciless streak indicates why Mourinho was prepared to wait for him, why he did not sign another forward in the January transfer window, why Chelsea’s summer business was planned with such meticulous farsightedness.

While others exhibited all the signs of panicking in a last-minute scramble for reinforcements on Monday, Chelsea have become an advertisement for good planning.

The unofficial signing-of-the-season contest kicked off long before many deals were done. It could boil down to a private duel at Stamford Bridge: Costa and Cesc Fabregas, signed for similar sums from Spanish clubs, have the potential to be equally influential.

One difference lies in their pedigree. The midfielder has been a top-class player for the best part of a decade. The striker had only proved truly prolific for one season before arriving at Chelsea.

Yet his 2013/14 campaign, encompassing 27 goals in La Liga and 36 in all competitions for Atletico Madrid, has undeniable similarities with Drogba’s sudden development 10 years earlier.

Late bloomers were transformed into strikers with the range of attributes to suit a Mourinho team. They arrived fully formed and it is worth remembering the Portuguese prefers players at their physical peak, their decision making honed by several years in the professional game.

Last year’s Chelsea side were not as young as their manager often implied. Rather, they were sometimes found wanting in the penalty area.

Eto’o had the nous but not the legs, Fernando Torres neither the clinical finishing nor the speed he displayed in his younger days and only Eden Hazard of Chelsea’s flair players scored often enough.

It is instructive to contrast Mourinho’s remodelling of his side with the Roman Abramovich-inspired purchases of wingers and attacking midfielders in the preceding transfer windows.

Whereas the owner, desperate for Torres to succeed, left Chelsea short-staffed in attack and overloaded with creators, the Portuguese has stiffened the spine of his side.

The outstanding Thibaut Courtois has returned from loan to become the first-choice goalkeeper, Fabregas and Nemanja Matic form the new midfield axis and the redoubtable Costa leads the line.

Abramovich always wanted a side with aesthetic appeal. Last season Chelsea scored at least 30 fewer goals than the two teams of centurions, Manchester City and Liverpool.

Now Mourinho is delivering a more prolific, more productive side but, personified by Costa, he is doing it his way.

There is nothing elegant about Everton’s tormentor, but he is hugely effective. That amounts to entertainment, Mourinho style.

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