This article is part of Football FanCast's The Chalkboard series, which provides a tactical insight into teams, players, managers, potential signings and more...

Chelsea were able to comfortably beat Southampton 4-1 at the weekend. In doing so, they looked assertive in the air, which has very rarely been the case so far this term.

On the chalkboard

The Blues won their fourth game on the bounce at St.Mary's Stadium on Sunday, with Tammy Abraham, Mason Mount, N'Golo Kante and Michy Batshuayi getting themselves a goal apiece.

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Of course, they were unable to keep a clean sheet, which has so often eluded them this campaign, but there was one defensive aspect in which they were significantly improved.

Aerial improvement

Set-pieces have been a big problem for Chelsea so far this term. They have conceded four goals from them in the Premier League, with only two teams shipping more, whilst they top the charts in Europe in this aspect too. With most corners and free-kicks coming into the box being aerial, prowess in the air would not go amiss. Frank Lampard's side, though, have won just 17.8 aerial duels per match, which is in the bottom half of the top tier.

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Against the Saints, there was a distinct improvement. The Blues faced 10 shots, of which five did come from free-kicks - but that number is slightly misleading considering it includes direct shots as well. From corners, though, the Blues were efficient, with all three the Saints took being headed away before they could find a player in red. From offensive situations, they were themselves dangerous, with all four corners finding one of their own players.

There was also a general improvement in the air overall, with no less than 22 aerial duels being won by the south-west London outfit. That is an increase of 4.2 on the average so far this term.

Of course, the Blues cannot afford to be complacent, and their recent troubles indicate that it could still be an issue moving forward. But the improvement is an encouraging sign for Lampard, especially considering he admitted it was a problem following the Lille match in the Champions League.

Maybe some of the training ground work has paid off.