Paris St-Germain midfielder Marco Verratti remains the top target at the Nou Camp but new manager Ernesto Valverde is looking at alternatives.
Spanish outlet Diario Gol claim the £100m cost of the 24-year-old could force the La Liga side to look elsewhere.
They say Coutinho, Alli and Herrera are the three options seriously being considered by top chiefs at Barca.
Coutinho would cost less than Verratti and is a close friend of Neymar who would welcome the Liverpool star's arrival.
Tottenham star Alli is the next name being considered after his impressive performances helped Spurs finish second in the Premier League last season.
And the third man being looked at is Manchester United ace Herrera who previously worked with Valverde at Athletic Bilbao.
Barca are also monitoring Paulinho and Jean Seri if their interest in the Premier League trio fails to materialise.
TRANSFER NEWS LIVE: All the latest rumours, gossip and every done deal
The Catalan club will want to have a much better season this time around after arch rivals Real Madrid won the La Liga title as well as the Champions League.
Liverpool, Tottenham and United won't sell their key players on the cheap though.
Coutinho, Alli and Herrera were all impressive for their respective clubs last season and will want to make an even bigger impact this year.
