Marquee matchup: Arsenal should hoof it to the back stick at Chelsea
Arsenal's first-half forage on Chelsea in September was a blessing in disguise.
It encouraged Antonio Conte to return to what had worked for him so well at Siena, Juventus, and Italy - a back three - and to banish Branislav Ivanovic (who went from leaping high enough to alert air traffic control in the 2014-15 season to turning like an aircraft carrier months later) in favour of the tireless Victor Moses.
Suddenly Diego Costa was more closely bordered in a front three, N'Golo Kante received more responsibility to quickly spring attacks after winning possession, and David Luiz could enjoy freedom and spring long passes with regularity.
Thirteen consecutive wins followed.
Since that 3-0 victory, the Gunners have gone on encouraging streaks, but have tended to underperform against their rivals in the top six:
| # | Team | Won | Drawn | Lost | Points |
|---|---|---|---|---|---|
| 1 | Liverpool | 3 | 4 | 0 | 13 |
| 2 | Chelsea | 3 | 1 | 3 | 10 |
| 3 | Tottenham Hotspur | 2 | 3 | 2 | 9 |
| 4 | Manchester City | 2 | 1 | 3 | 7 |
| 5 | Manchester United | 1 | 3 | 2 | 6 |
| 6 | Arsenal | 1 | 2 | 2 | 5 |
That was until the midweek visit from free-falling Watford took a worrying turn: a 2-1 loss on home soil where Arsenal players were exposed for cutting corners and appeared rather aloof throughout the tie.
Against Chelsea, a performance like that would be heavily punished.
Injuries and suspensions
Once again, the treatment room at Chelsea's Cobham training ground is collecting cobwebs. There are currently no sick notes being passed to Conte.
Mohamed Elneny is still at the Africa Cup of Nations and Granit Xhaka is suspended, so Alex Oxlade-Chamberlain may operate as an auxiliary defensive midfielder for Arsenal. Mathieu Debuchy and Santi Cazorla are long-term concerns, and Aaron Ramsey is expected to miss three weeks with a calf strain.
Projected lineups
Chelsea starting XI: Courtois; Azpilicueta, Luiz, Cahill; Moses, Kante, Matic, Alonso; Pedro, Costa, Hazard
Arsenal starting XI: Cech; Bellerin, Mustafi, Koscielny, Monreal; Oxlade-Chamberlain, Coquelin; Walcott, Ozil, Sanchez; Giroud
What to watch
Mirroring Chelsea's 3-4-3 formation almost worked for Manchester City in December, then worked superbly for Tottenham Hotspur when it beat the Premier League leader 2-0 at White Hart Lane.
But a 4-2-3-1 has become as much as Arsene Wenger's makeup as donning a coat resembling a sleeping bag and maintaining ignorance of contentious events involving one of his players, so Arsenal's game depends on the personnel the Frenchman chooses.
Olivier Giroud can frustrate at times, and deploying him means Alexis Sanchez will again vacate the false nine slot where he operated so successfully over the first half of the season. Since Giroud's first Premier League start of the campaign on Boxing Day, Sanchez's output in the division has dropped from 0.75 goals per start to 0.5. It all adds up.
The bonus of fielding Giroud, however, could be capitalising on Cesar Azpilicueta's inferior height and Moses' relative inexperience in offering defensive help. Spurs took advantage of this in each of Dele Alli's headers in Chelsea's hiccup last month, and it was something Liverpool purposely exploited when James Milner, ghosting in at the back stick, nodded across to goalscorer Georginio Wijnaldum on Tuesday.
"This space where we scored the goal, we wanted to have more crosses," Reds manager Jurgen Klopp confessed after the 1-1 draw.
Arsenal can use a copycat route at Stamford Bridge, getting target man Giroud to arc runs to the back stick. Around him, Sanchez could either burst into the middle to meet a ball nodded across, or loiter deeper than the rest of the attack-minded players - as he's tended to do recently - and draw Luiz out of the back three. The Brazilian went chasing a withdrawn Roberto Firmino last time out, seconds before Wijnaldum took advantage of the positional confusion that ensued and headed home.
To deliver the ball into the Giroud zone, Tottenham had Christian Eriksen, and Liverpool had Jordan Henderson or Nathaniel Clyne. If Wenger opts for this plan, he will likely elect Theo Walcott - who can air balls with greater accuracy than Alex Iwobi - and Hector Bellerin as his chief crossers.
Ultimately, Chelsea will be the favourite for this meeting, so Arsenal has to have a defensive midfield that can bite, harry, and then feed the ball to the attackers. Simple stuff, but criteria that weren't satisfied by Francis Coquelin and, in particular, Ramsey last time out.
Alex Oxlade-Chamberlain filled in well there against an under-strength Southampton in the FA Cup last weekend, but the jury's out on whether he can successfully help crowd out that vital area between the Gunners' midfield and defence - exactly where Eden Hazard and Pedro lurk behind Costa.
Three points will be expected for the Blues but, given their supremacy in England so far, a point would suffice with some winnable encounters on the horizon.