Premier League leaders Chelsea maintained their seven-point advantage at the top of the table with a dramatic late win over Roberto Martineza s resilient Everton side. An 89th minute strike from Brazilian midfielder Willian secured all three points for the Blues, who also had their goalkeeper Petr Cech to thank for the result. The Blues are now firmly in the driving seat going into the final third of the season, thanks largely to their outstanding home record a winning eleven and drawing just one out of their twelve league fixtures at the Bridge.

Despite being unable to take any points back to Merseyside, Everton did have plenty of positives to take away from the game a particularly the performances of 20-year-old English centre-back John Stones, and returning veteran goalkeeper Tim Howard. Whilst a poor first half of the season means that the Toffees will not have any designs on a European place this term, a strong finish would go a long way in laying the foundations for a possible European challenge next season.

In a game that had plenty of talking points and several stand-out performances, here are four things we learned:

1) Willian is rapidly becoming a Mourinho a untouchablea

The last few days of the January transfer window saw a flurry of transfer activity at Stamford Bridge, with Juan Cuadrado signing from Italian club Fiorentina, whilst Andre Schurrle was shipped off to Bundesliga side Wolfsburg. Cuadradoa s arrival was widely seen as a threat to Williana s place on the right wing in Chelseaa s 4-2-3-1 formation, and recent performances would suggest that the Brazilian was well aware of that. The former Shakhtar Donetsk attacker has upped his game and been instrumental not only in getting Chelsea to the Capital One Cup final, but also in extending their lead at the top of the table.

Whilst his immense defensive work-rate and unrelenting intensity are the most talked-about aspects of his game, Willian has been improving steadily in an attacking sense as well. His late goal against Everton at Stamford Bridge followed his assist for Eden Hazard at Villa Park, as well as his cross that set up Branislav Ivanovica s header in Chelseaa s extra-time win over Liverpool in the Capital One Cup semi-final.

Willian is the quintessential Mourinho player a his ability to carry out instructions to the tee makes him a priceless asset to the Chelsea set-up. Even though he does not often stand out in a team that boasts quality all over the park, he is probably amongst the first names on the Chelsea team sheet. His pace in attacking transitions when Chelsea are playing on the break, as well as his ability to close down opposition and win the ball back high up the park make him crucial in a tactical sense regardless of the style of football Mourinho opts to play against a particular opponent. The Brazilian international was able to cap his typically industrious performance against Everton with the winning goal, earning him well-deserved a and long overdue a plaudits from the fans and media alike. Willian is growing in stature at the club after a quiet start, and is quickly becoming a Mourinho a untouchablea .

2) Petr Cech will keep Thibaut Courtois on his toes this season

Chelsea 1 Everton 0 a   Four Things We Learned From the Bluesa   Dramatic Win at the Bridge

Thibaut Courtois will be wary of losing his spot to Petr Cech if his performance levels were to dip

Chelseaa s legendary Czech goalkeeper has five clean sheets from five games so far this season, and is just three away from breaking David Jamesa all-time Premier League record of 170 clean sheets. Blues manager Jose Mourinho explained his decision to start his former no.1 against Everton, saying a I played Cech because Courtois played consecutive matches and needs to be focussed. A goalkeeper can be tired, not just physically, but also in the nervous systema . Whilst that may be a perfectly logical explanation, Cecha s game-saving performance means that the Belgian no.1 cannot, even for a moment, take his position for granted.

Petr Cech is, by some distance, the best no.2 keeper in England, if not all across Europe. On Wednesday night, he was arguably the main reason Chelsea were able to claim all three points against Everton. With the score at 0-0, he made not one, but two superb saves to deny Romelu Lukaku a the second a truly breath-taking reaction save from point-blank range. With Courtois having a couple of somewhat uncertain performances between the sticks against Manchester City and Aston Villa, this performance from his senior team-mate would have made him sit up and take notice. If he had not already considered the Czech a potential threat to his position, he certainly will from this point on. Cecha s presence at the club will keep Courtois on his toes, and the biggest beneficiaries of this healthy competition will ultimately be Chelsea.

3) Everton could be more successful as a primarily counter-attacking team

After guiding Everton to their highest league position in Premier League history last season, former Wigan boss Roberto Martinez is having a season to forget this term. Whilst injuries have affected him this season and the defence has been poor, the Spaniarda s tactical rigidity is arguably the main reason the Toffees find themselves in their current predicament. Despite signing Romelu Lukaku and Gareth Barry on permanent deals following extremely successful loans last season, and adding Bosnian World Cup star Muhamed Besic to their midfield ranks, Everton are languishing in 12th place in the league table, having been knocked out of all domestic cup competitions.

The Toffeesa possession-based football a whilst effective when the team is confident and moving the ball around quickly a has been found out this season, in part due to their slow, ponderous play in the attacking third, but also because it might not be the best fit for the players they possess. In Lukaku, Kevin Mirallas, Steven Naismith, Ross Barkley and January recruit Aaron Lennon, Everton have some serious pace in their side. Combined with the midfield steel that Barry, Besic and James McCarthy provide, the Merseyside club would perhaps be best served by playing quick, counter-attacking football a somewhat in the style of Borussia Dortmund under Jurgen Klopp.

In Gareth Barry, Everton have a midfielder who has the passing range to pick out quick passes to the forwards in attacking transitions. In Lennon, Barkley and Mirallas, the Toffees have three players that can almost bypass opposition midfields with the pace they possess. Above all, it is the style of play that brings the best out of A?28m man Romelu Lukaku. Martinez has shown in the past that he is not averse to the idea of playing on the break a his 3-0 win against Arsenal at Goodison Park last season a perfect example of how reactive football can be both effective and attractive at the same time. On that occasion, Lukaku caused absolute havoc amongst the Arsenal ranks with his strength, pace and directness.

The Belgiana s hold-up play is decidedly average, as is his first-touch. As such, he is almost entirely ineffective with his back to goal. Kurt Zouma gave him very little breathing space in Wednesday nighta s clash, and for the most part, did not allow Lukaku to turn, keeping him quiet for the majority of the game. However, when Lukaku picked up the ball in space and ran at the Bluesa defence, he did look like he could cause them some serious problems. Given Everton have very little to play for in the league this season, Martinez has the option of making tactical changes and experimenting a little, and this might be something for the Spaniard to ponder.

4) Chelsea are showing the belief of champions

Maturity and belief. Those are the qualities manager Jose Mourinho pointed to when asked how his side is different compared to last season. Following the 1-0 defeat to Crystal Palace last season that all but ended Chelseaa s title hopes, Mourinho famously wrote down for a journalist what he thought his side were missing: a Ballsa . Despite losing to Newcastle away from home yet again, the Blues this season have won at Selhurst Park, Goodison Park as well as Villa Park a places where they were defeated last season. In games against smaller sides that Chelsea were unable to break down last season, the Blues have found a way this time around, thanks in no small part to the contributions of midfielder Cesc Fabregas and the leaguea s top scorer Diego Costa.

Chelsea 1 Everton 0 a   Four Things We Learned From the Bluesa   Dramatic Win at the Bridge

This Chelsea side are displaying the maturity and belief of champions

It is a true testament to their belief, then, that Chelsea were able to see out a gruelling, intense period of fixtures without Fabregas and Costa, including a clash against champions Manchester City , whilst not only maintaining their position atop the league, but in fact extending their lead. Recent games against Aston Villa and Everton followed a similar pattern a late winners following performances that were not amongst the cluba s best this season. However, Mourinhoa s side kept pushing right till the very end in both games, and got their just reward. The additions of Cesc Fabregas, Diego Costa, Filipe Luis and Didier Drogba as well as the availability of Nemanja Matic from the beginning of the season have gone a long way towards adding that extra bit of leadership and maturity that Mourinhoa s figurative a little horsea needed to be real contenders this season.

Chelseaa s football this season has varied from fluid and silky to downright nasty and in-your-face aggressive. They arena t making too many friends along the way this season, but that is probably just as Mourinho planned it. His side are showing all the signs of achieving something special come the end of the season.