The Bayer Leverkusen star has been linked with a possible move to Goodison Park.
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Primarily a left winger who can also play on the right, Diaby has scored four Bundesliga goals this season and also laid on 12 assists.
Diaby has genuine pace to burn and also has plenty of trickery to offer, and Ball believes that bringing in a player of his quality would genuinely improve Everton.
He said: “Diaby is all pace, it’s a great outlet. Everton usually like playing on the front foot, especially at home, and they haven’t had those types of players at the club this season to play in that style.
“And I think his assists this season have been very high. If we look at who Everton have got at the moment, I think Richarlison has only had three or four assists this season which is not good if you want to be touching top four or top six. I think Diaby’s got 10 or 12 assists this season, played a lot of games.
“So for the recruitment style, he’s going to cost money but they’ll have a lot of data.”