The Brazilian was impressed with the former Swansea City playmaker's first training session and is confident that he can be an important asset at Anfield this season
Allen became new boss Brendan Rodgers' second summer signing following Italian striker Fabio Borini's arrival on Merseyside and it appears that he has already settled in at Anfield.
Lucas, who is likely to line up alongside the Welshman in central midfield, has claimed that his new colleague's quality was there for all to see when he joined up with the squad for the first time.
|2/1||Joe Allen is 2/1 with William Hill to score between 4-5 league goals for Liverpool in 2012-13
"He had a training session with us and we can see what a quality player he is," the Brazilian told the club's official website.
"Hopefully he can be a key player for us during the season."
The Reds kick off their 2012-13 campaign at the Hawthorns on Saturday when they face Steve Clarke's West Brom, having also continued their progression in the Europa League by beating FC Gomel.
And Lucas acknowledges that the added depth that Allen will offer in midfield could prove vital over the coming season.
"It's one more player to fight for a place and it's really good for the club. We need more than 11 players to be successful," he added.
"He had a good season last year and he had a great tournament in the Olympics as well. He has confidence and he has experience so hopefully he will do well for us."