Chelsea were nearly robbed yet again by debatable officialdom in Basle, but a David Luiz last-kick goal ensured they took a lead into next Thursday's Europa League semi final second leg.

Blues were almost left complaining about decisions that had cost them another win, four days on from their controversial draw at Anfield.

A highly dubious 88th minute penalty awarded against Cesar Azpilicueta, for what seemed to most like a perfectly acceptable challenge on Valentin Stocker, leveled the scores and set Blues' temperatures racing.

But a free kick from Luiz right at the last ensured they took the full advantage of an away win back to Stamford Bridge.

Blues 'interim' boss Rafael Benitez did the expected thing, and rotated his squad again. Back in came Frank Lampard and John Terry, with Victor Moses also joining the fray.

Joh Mikel Obi, Juan Mata and Oscar were among those benched for the occasion.

With a dozen minutes on the clock, a Chelsea corner sailed just beyond a leaping Branislav Ivanovic, to hit Victor Moses on the head and go in. Header or rebound – they all count the same: and the Nigerian cartwheeled away in celebration.

The first half developed as a familiar story: Chelsea making plenty of chances, but wasting so many of them.

Meanwhile at the other end, risque defending saw Basel break through a number of times – on each occasion either fluffing their won chance, or seeing Petr Cech ably cover it.

Chelsea, often a side lacking concentration immediately after the break, almost paid for just that sort of lapse: Stocker's swerving shot hitting the base of Cech's post right after the interval.

Chelsea themselves threatened the woodwork less than ten minutes later: Fernando Torres, still in his mask, thwacked a ball from Eden Hazard against the upper part of the upright, when it looked easier to score.

Referee Pavel Kralovec, following a reasonable first half, made some odd decisions after the break.

A yellow card for Ashley Cole for time wasting put him out of the second leg; while the same punishment issued to Aleksandar Dragovic may have had the same effect – but many were calling for a great deal more for his two-footer on Torres.

But the official had his most haphazard decision of the night still to come. With three minutes of the 90 remaining, he awarded the penalty – few could see any real case to back-up the decision.

Fabian Schar converted from the spot.

In truth, had that been the end of the story, Blues could have blamed their own wastefulness as much as the poor decision of the official.

But they saved that argument for another day, with Luiz' winner.

With an away win under their belts, Chelsea will be favourites to make next month's final in Amsterdam. But that will count for nothing if they refuse to bury the complacency that has become so much a part of many recent winnable contests.

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