Betis had a dream start when Abde Ezzalzouli smashed the ball in off the crossbar on six minutes following battling centre-forward play by the in-form Cedric Bakambu.

Fiorentina came within a whisker of equalising midway through the first half, but Rolando Mandragora's powerful header zipped inches wide of goalkeeper Fran Vieites' upright.

Former Barcelona centre-half Marc Bartra had a chance to double Betis' lead at the end of the first period but blasted over from a corner.

Manchester United loanee Antony then did get a second for the hosts with a fierce right-footed effort from outside the box which flew beyond David de Gea's reach and into the top corner in the 64th minute.

Fiorentina halved the lead against the run of play with 17 minutes remaining as Luca Ranieri slotted home after being teed up by Robin Gosens.

The second leg ties will take place next Thursday.