London - Andre Villas-Boas can become the first opposition coach to plot Chelsea's downfall in a Premier League match this season when his old club play his in-form Tottenham Hotspur side at White Hart Lane on Saturday (1145).
The 34-year-old Portuguese is gradually rebuilding his reputation at Spurs after enduring a traumatic nine-month spell that lasted for just 27 league matches at Stamford Bridge before his dismissal in March.
The London derby is the oustanding game of the weekend and offers him the chance of some personal revenge with extra spice added to the mix.
Chelsea finished sixth last season, two places behind Spurs, but they took Spurs' place in the Champions League after winning the final itself in Munich, consigning Spurs to the Europa League despite finishing in the top four.
Chelsea became European champions under Roberto Di Matteo who went to Chelsea as Villas-Boas's deputy in the summer of 2011 and took over as boss when he left.
Chelsea go to Spurs as leaders on 19 points after winning six and drawing one of their seven games while Spurs have climbed to fifth on 14 points after winning their last four league games - including their 3-2 success at Manchester United, their first win at Old Trafford for 23 years.
If Spurs were to halt Chelsea's progress, Manchester United, champions Manchester City and Everton would all be looking to capitalise.
United, second on 15 points, are at home to mid-table Stoke City, Manchester City third on 15, visit sixth-placed West Bromwich Albion and fourth-placed Everton face bottom-of-the-table Queens Park Rangers.
All eyes though will be focused on White Hart Lane on Saturday lunchtime where Spurs are seeking to extend their unbeaten run to 10 matches in all competitions since an opening day defeat at Newcastle United in August.
Their last victory came two weeks ago before the international break when they beat Aston Villa 2-0 at home, a result that delighted "AVB".
"This gives us the opportunity to play the league leaders at home, undefeated for a while and with a good chance to go nearer the top," Villas-Boas said.
"It is obviously going to be a difficult game but we are showing a good level of competence."
Chelsea have not won at White Hart Lane in their last six Premier League visits but did beat them 5-1 in their last meeting, an FA Cup semi-final at Wembley last season.
Villas-Boas is optimistic.
"They have a lot of very young, dynamic players but so do we, and we are playing very well right now. This is a very good moment for us to play them."
With many players away on international World Cup duty over the past week, coaches will be waiting with baited breath to see who comes back fit and healthy, but Chelsea already have doubts about Frank Lampard (shin) and Ryan Bertrand (illness).
Manchester United are still suffering a long injury list, but there is a chance that Ashley Young (knee) and Chris Smalling (foot) could be nearing a return.
Manchester City travel to The Hawthorns without David Silva, who is still struggling with a muscle injury and Jack Rodwell, who has a hamstring problem.
They should have Mario Balotelli back and raring to go after he scored for Italy in their 3-1 win over Denmark on Tuesday and then said he was enjoying life at City, despite the club's sporting director Brian Marwood criticising his attitude and behaviour.
Balotelli told Italian TV station Rai: "I'm fine at Manchester City even though there are a people who like to talk to the newspapers rather than say things to my face. I don't give a damn.
"All is well with (coach) Roberto Mancini and we have a good relationship. We love each other."
Arsenal have slipped back to seventh on 12 points, but are never out of contention for a top four place and should keep up the pressure on the leading pack when they travel to second-from-bottom Norwich City, still looking for their first League win of the season.
Arsenal are likely to be without Theo Walcott, who suffered a chest injury playing for England against San Marino on Friday, but their France striker Olivier Giroud will be eager to repeat his recent scoring feats.
He scored his first League goal for Arsenal in their 3-1 win at West Ham, and also scored for France with a last-gasp header to earn a 1-1 draw with world champions Spain in their World Cup qualifier on Tuesday.