Change and opportunity in defence
For the umpteenth game in a row, Pep Guardiola will be unable to call on the same Manchester City defence for successive games.
Such continuity was vital to their charge to the title in the run-in last season but it simply hasn't been possible this season ever since Aymeric Laporte suffered that serious injury against Brighton in August. Nine games have followed and not once has the manager not made at least once change between games - some through choice, plenty through injury.
Rodri's hamstring problem makes another guaranteed against Aston Villa while Aleks Zinchenko's absence further limits options but there is a silver lining for Guardiola. For the first Premier League game since the win at Crystal Palace more than six months ago on April 14, he could line up with a left-back, two centre-backs and a right-back. There's Benjamin Mendy or Angelino, John Stones and Nicolas Otamendi (plus two youngsters) and Kyle Walker or Joao Cancelo, all fit enough to start.
Guardiola may of course choose not to do that; Fernandinho, for instance, is being treated as a central defender for the season after the club failed to sign one in the summer window. But in a week where it has felt like more injuries have hit the Blues, a reminder that it is not all bad news.
Villa confident
Guardiola has spoken before of the dangers of playing promoted teams early on - as Norwich showed - and Villa have got their tails up. A draw at Burnley was followed by a thumping win at Norwich and a last-gasp win over Brighton last time out to mean Dean Smith's side have seven points from their last three games - more than City.
This should be a home banker and the chance to close the gap temporarily at the top of the table to three points, a chance to reassert the authority of the champions following defeat to Wolves last time out at the Etihad. Anything but a win and there will be more talk of frailties.
Fire vs fire
Villa have certainly entertained in the league. Only four teams have managed more than their 15 goals this season, while only five teams have conceded more than their 13 goals.
That suggests Saturday's game won't be short of goals, which means City will have to heed their manager's regular warning and be good in the boxes. Finish like they did against Atalanta and they should be fine but if they are as wasteful as they were at Crystal Palace that will leave an opportunity for the visitors to punish them.
