Fluid Chelsea attack has inevitably left them vulnerable to counterattacks

Shakhtar Donetsk threatened Chelsea with swift counterattacks all evening as the Ukranian side dominated play in a 2-1 Champions League win. The win puts the Ukrainian side 3 points clear of Chelsea at the top of group E and puts a great deal of pressure on the Blues to win the return home fixture in a fortnight if they're to qualify for the knockout stages.

Both teams lined up in 4-2-3-1 formations. Frank Lampard was given the start alongside John Obi Mikel as a deep lying midfielder. Ramires shuffled to the right attacking midfield position, presumably to provide defensive help to Branislav Ivanovic on the excellent Willain, while Eden Hazard started the game on the bench. There were no surprises in Mircea Lucescu's starting 11.

Lampard picked up an injury 18 minutes in and was replaced by Hazard. Ramires dropped back to Lampard's position in the center of midfield and Hazard played on the right, the lineup Chelsea have used most of this season.

For the second consecutive game Chelsea were vulnerable on the counter. While Chelsea were fortunate that Moussa Dembele and Gareth Bale were out of Spurs' lineup in their 4-2 win at the weekend, they still at times appeared susceptible to quick counters when they lost possession in what was a rather open game. The problem was even more pronounced last night as Willian, Alex Teixeira and Henrik Mkhitaryan were able to get in space behind Mikel, Ramires and outside backs Ivanovic and Cole on the break and run at the center backs.

The space that opens up between Chelsea's two holding midfielders and center backs has been an issue all season. When Mikel is forced to push into a more advanced position to offer a passing option for the front four, the center backs have stayed rather deep creating a big pocket of empty space. When Chelsea lose possession, the opposition has been able to play quick outlet passes to teammates moving into that space, setting off dangerous counters. As they showed last season under Villas-Boas, Chelsea are not comfortable squeezing the space the opposition has to play in when possession is lost by pushing the defensive line forward and pressing (like Barcelona). Instead, their defense tends to drop deeper when they lose the ball.

This is understandable. John Terry's lack of pace makes him vulnerable to balls in behind him when he presses forward and Chelsea's experimentation with a high line last season was disastrous (the 5-3 Arsenal loss the clearest example). But because Mata, Hazard and Oscar are typically not quick to make defensive recovery runs, loads of space opens up in the middle third of the pitch for their opponents to move into- this explains why Chelsea's last two games have been so open. The issue is, effectively, that the back six and front four have been rather disjointed defensively. While this shape has given Chelsea's three advanced midfielders the freedom to focus more on creating scoring opportunities than worrying about defensive responsibilities, it has made them a less compact side defensively.

The new, more fluid attacking system has produced some breathtaking displays thus far and few Chelsea supporters will be calling for a return to the defensive tactics that won them the Champions League last season. However, they'll likely continue to look vulnerable on the break as they adjust to the new system.