The Blues went into the game on the back of three straight top-flight wins, the last of these being an impressive 1-0 defeat of Manchester United, while the Baggies were pointless over the corresponding period.

That said, Chelsea's uncanny knack of underperforming against supposedly feeble teams had already infuriated fans on a couple of occasions this season. The opening day 3-2 home defeat to Burnley owed much to ill-discipline, however the 2-1 loss at bottom side Crystal Palace was gutless. Against the Eagles, the Blues lacked inspiration and a cutting edge and following the embarrassing performance at Selhurst Park pressure mounted on manager Antonio Conte. It looked set to get worse for the Italian next time out when Watford took a 2-1 lead at the Bridge, but his players turned it around to win 4-2 and it's been all smiles since.

The catalyst for Chelsea's change in fortunes and the reason they played at the Hawthorns with no fear can be largely attributed to the fact that playmaker Eden Hazard and striker Alvaro Morata are both back to full fitness and able to play in tandem together.

Hazard who missed the opening part of the season, having picked up an ankle injury while on international duty with Belgium in June, was sensibly eased back into the fray by Conte, who knew full well that the 26-year-old would be kicked from pillar to post by opposing teams unable to contain him by any other means.

Hazard picked up his first Premier League assist of the campaign against Watford, a game in which Morata, having just returned from a hamstring injury suffered in the home defeat to Manchester City that kept him out of the subsequent loss to Palace, featured for an ineffective hour.

Prior to getting injured, the Spain international had already justified his status as Chelsea's record signing by scoring six league goals and providing a couple of assists. When fully fit, the hope and expectation of Blues supporters and Conte no doubt was that the 24-year-old would soon get back in a goal-scoring groove. The big question was could Hazard and Morata work effectively together? The answer, a resounding yes, would be proven next time out in the league against Bournemouth.

Assisted by Morata, Hazard scored the only goal of the game in a 1-0 win at the Vitality Stadium and also created seven chances for his teammates, among them several for the Spaniard, who found the net on one occasion which was ruled offside.

Next up in the league came Manchester United and it was Morata's turn to grab the headlines with a spectacular headed winner. As expected, Hazard was on the receiving end of some hostile Man United tackling, but fortunately he came through unscathed ready to run the gauntlet once again at the Hawthorns.

Shrugging off the effects of a heavy early tackle from Gareth Barry that left him floored and then limping, Hazard was soon at his defence-shredding effervescent best, drawing a save from West Brom keeper Ben Foster. Morata picked up the loose ball and smashed it into the net.

Morata then turned provider for Hazard with a deft piece of vision and skill that presented his teammate with the opportunity to take on and beat Foster; Marcos Alonso added a third goal before Hazard perfectly controlled a through ball from Cesc Fabregas to score his second and Chelsea's fourth of the game.

The telepathic relationship that Morata and Hazard have developed owes much to the striker's fondness for operating in the left channel where the creative midfielder can be found attempting to drift clear of attention. Speed and tactical awareness is a feature of both players' games and they clearly feed off each other's energy and enthusiasm.

Hazard and Morata remaining injury free appears key to Chelsea's chances of staying in touch with Manchester City -- who have a nine-point advantage over the Blues at the top of the Premier League table. The duo will also have a marked influence on the London club's chances of winning silverware in other competitions this season.

Though Conte can only pray that Hazard and Morata remain fit, especially given the demanding fixture schedule Chelsea now face, the Blues boss can play a part in influencing the way they react to the physical attention and niggling fouls their ability attracts.

Against West Brom, both players were booked by referee Jon Moss for reactionary challenges and suspension would be a needless way to hand an advantage to any given opponent in the future.