Diego Costa Chelsea
Chelsea striker Diego Costa celebrates after scoring the winner against Leicester City in the English Premier LeagueReuters

Diego Costa was substituted on 80 minutes to the most deafening of applause, as Stamford Bridge legend Dider Drogba made his return home, but not before the new summer signing took his first few steps towards emulating the living legend by scoring the winner to give Chelsea a hard-fought 2-0 victory over battling, impressive Leicester City in the English Premier League.

After a frustrating first half, the level of play was lifted ten-fold in the second 45, with Chelsea, let-off a couple of times by David Nugent and some outstanding goalkeeping by Thibaut Courtois, making that pressure pay via a Costa strike, before Eden Hazard got his trademark goal to put the gloss on a satisfying afternoon.

Following that impressive display in their opening Premier League game against Burnley, expectations were high with Jose Mourinho naming the same starting lineup that strolled to victory at Turf Moor on Monday.

However, the difference in this Premier League is so little that if you step down your level by just that little bit, and the opponent play up to their optimum level, you will be in for a tough encounter. And that proved to be the case, especially in the first half for Chelsea, with Leicester giving as much as they received, and maybe even shading it on chances and forward-thinking verve.

Leicester City manager Nigel Pearson said his team would not sit back and let Chelsea dictate the pace heading into the game, and that proved to be far from a hollow claim as the away team, coming off a 2-2 draw against Everton on opening day, took the match to the home side whenever given an opportunity.

While clear-cut chances were very much at a premium, Leicester were not short on attacking intent with Riyad Mahrez coming up with the best chance of the first half for either side with a nice strike from 23 yards after creating a little bit of space outside the area.

Chelsea again looked to Cesc Fabregas for inspiration in the final third, and while the former Arsenal and Barcelona man was not quite as effective as he was against Burnley there were a few glimpses of his class with a couple of passes -- one to Diego Costa and another to Schurrle, the man whom he found for the winner against Burnley – nearly carving the Leicester defence open.

One of the issues that Mourinho might want to sort out is that fact that because Fabregas is seeing so much of the ball, it does put Hazard, their main man from the last couple of seasons, a little bit on the periphery. There were a couple of times when the Belgian did those now expected shift-of-the-ball-and-cross-from-the-left, but they were few and far between.

The Blues' best opportunity was created by Hazard, though, with the playmaker showing a bit of trickery down the right before finding Costa, whose shot, which looked like it might trouble Kasper Schmeichel, deflected high.

Mourinho would have expected more from his side in the second half, and he certainly got it as Chelsea cranked up the pressure right from the off, with Leicester, once again, not shying away from pouring forward either.

Oscar nearly opened the scoring, cutting in from the right on the edge of the box before curling a wonderful low strike past Schmeichel, with the ball deciding to strike the post instead of nestling into the bottom corner.

Chelsea weren't done on that attack, though, as Branislav Ivanovic, who had an inspired second half going forward from right-back, forced a nice save from the Leicester goalkeeper with a header which was heading into the top corner.

Andre Schurrle then tried his best to ripple that net by doing what Oscar did moment ago, with his effort flying high above Schmeichel.

As Chelsea poured forward in search of the opener, space was always going to open up at the back for Leicester to counter, and had Nugent got his goalscoring boots on, then the result might have been completely different.

The former England international had two wonderful chances, both off breaks, with two saves from Courtois thwarting the forward from finding the back of the net.

First came on a three-on-two situation with the ball falling to Nugent, whose strike from the edge of the penalty area was well kept out by the feet of Courtois. The Chelsea goalkeeper, in the spotlight after being preferred for Petr Cech, would put his feet to good use again to deny Nugent, with the striker seeing his shot, from a one-on-one situation, brilliantly kept out.

In between those two chances, Ivanovic had another crack on goal with Schmeichel again doing wonderfully well to deny him. At the third time of asking, though, Ivanovic would find a way through, with his cross from the right falling to Costa, who chested it down before poking the ball home on 63 minutes.

Chelsea just relaxed that little bit after that goal, with Mourinho reinforcing his midfield by bringing on Ramires, back from a four-match suspension, for Schurrle, and the match was put to bed 13 minutes from time by Hazard, who made that trademark run from the left before slotting home with his right foot.

With the match done and dusted, there was time for the Chelsea fans to rise as one to welcome back one of their greatest as Drogba came on for Costa to a rapturous ovation to put the icing on the took-a-bit-of-time-but-got-there sweet cake.

Other results: Swansea 1-0 Burnley; Southampton 0-0 West Brom; Crystal Palace 1-3 West Ham; Aston Villa 0-0 Newcastle.