Siena's chances of staving off relegation from Serie A this season have taken a blow with a 1-0 home defeat to Chievo.
The Flying Donkeys started the contest brightly, with Isaac Cofie and Boukary Drame going close to breaking the deadlock in the opening minutes.
Siena also had a couple of good chances, both of them falling to Alessandro Rosina, but it was Chievo who broke the deadlock on the stroke of half time.
The visitors from Verona surged on a counter-attack and Sergio Pellissier latched on to Perparim Hetemaj's through-ball to flick over the on-rushing Gianluca Pegolo and into the net.
Simone Vergassola had a good chance to restore parity right after the restart but fired over the bar from close range.
Siena thought that they had equalised on the hour mark when Massimo Paci headed in Rosina's corner, but the referee controversially ruled it out.
Paci and Innocent Emeghara had chances for the home side as the second half progressed, but failed to earn anything from the contest.