The Argentina midfielder was rated one of the signings of the season last term.
Bomber told the WBA website: "Claudio Yacob had an incredible season.
"A lot of people have been crying out for us to get someone in who can protect the back-four for many years.
"Now we have someone who has done that superbly.
"He's patrolled that midfield and he has made life easier for the back-four.
"A lot of the things he does might go unnoticed to some people, but I'm sure his manager and his team-mates know how important he is to the team.
"I've taken to him big time."