Aston Villa have confirmed the signing of Czech Republic international striker Libor Kozak on a four-year contract.
The 24-year-old, who was top-scorer in last season’s Europa League with 10 goals, is believed to have cost around £5m.
He becomes Villa’s seventh new signing of the summer.
Manager Paul Lambert said: "We've been on this one for the last few months, trying to bring him to the Club, so I'm delighted to get it across the line.
"Libor has an unbelievable scoring record in the Europa League, incredible really.
“He wasn't given much opportunity for Lazio in Serie A but he showed proper potential in leading the line there at a strong club with a great tradition and we need somebody like him as we only have Christian Benteke really as a main target man.
"He'll take that burden off Christian and he'll add greatly to what we've got, with the likes of Nicklas Helenius, who's a different type of player, Gabby Agonlahor, Aleks Tonev and Andi Weimann in that area of the pitch where we can hurt teams.
“Libor's powerful, too, and I'm looking forward to working with him. We needed to bring in someone like Libor to help the overall philosophy to work.
"It's a matter of him now integrating with the group, which he'll do. We've brought in seven players this summer and we're trying to build the squad. It's getting there, no doubt about that and we'll keep building it."
Kozak, who stands at 6ft 4in tall, said: "I'm really happy to be at Aston Villa and I'm ready for this new step in my career.
"I hope it's a good step for me and also for Villa because everything is about the team. This is a big club, a very historic club with a fantastic fanbase and, for me, this is really important.
“From when I was a young boy, I have dreamt of playing in the Premier League and to do this with a club such as Villa is incredibly motivating. It's real now and I'm very happy about this.”
Kozak joined Lazio in July 2008 from Czech Second Division side Slezsky FC Oprava.