Villa complete deadline day swoop for striker Kozak
The 24-year-old top scorer in the Europa League last season with 10 goals, Kozak put pen to paper on a four-year deal to 2017 and the Villa manager emphasised the powerful addition his seventh summer signing will be as his evolving, young squad seek to build on a solid start to the season.
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 won the first of his four caps for the Czech national team in a November 2012 friendly against Slovakia. He has scored one international goal - in the Czech Republic's most recent game against Hungary last month in Budapest - and he is eager to work hard for Villa in the Barclays Premier League and tap into the experience he has acquired from playing alongside the likes of Lazio's Miroslav Klose.
"I'm really happy to be at Aston Villa and I'm ready for this new step in my career," said the 6ft 4ins Kozak.
"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.
"I leave it to others to speak about me but I hope I can help Aston Villa in the games and I hope to score goals as well. I will speak about Villa and the Premier League to Petr Cech and Tomas Rosicky on international duty and I'm sure they will be able to tell me really good things from the games they have played against Villa this season. Yes, I scored goals in the Europa League last season and I'm happy about this because it's not easy but I know it won't be easy either to score goals in the Premier League so all my focus will be on this now.
"Playing with such a strong player as Miroslav Klose, I hope I was able to learn something from him and I also hope, with this experience, to help improve Aston Villa. My ambition is to contribute as much as I can to the team, to score goals and to fit in with my new team-mates. I know I must also play well for the manager. I spoke to him, he said he's happy that I've arrived here and he wants me, which is very important. I'm really looking forward to this new step and challenge."
Kozak joined Lazio in July 2008 from Czech Second Division side Slezsky FC Oprava. He went out on loan after a season with the Rome club to Serie B side Brescia where he scored four goals in seven starts and 22 appearances from the bench.
He returned to Lazio where he has played 79 times in all competitions, scoring 22 goals.
Kozak was the top goalscorer in the 2012-13 Europa League with 10 goals. He scored a hat-trick against Stuttgart in Rome to send Lazio into the quarter-finals of the competition where they lost to Fenerbahce.
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