De Guzman has seen plenty of Hernandez after also playing in Spain last season, and believes he would be successful at the Liberty Stadium.
"He would be a great signing. He's a very good player, creative and fast," said De Guzman.
"I've played against him in La Liga where he was one of the key players for Valencia
"Every time I saw him play he impressed me.
"He's creative, he's fast and he can score goals from the left wing."