"Robshaw has had a wonderful season, but he has looked tired since the Wales game, he has looked tired, he has looked like a ghost of his former self," Barnes told Sky Sports News.
"But I think he could do a job at seven, or he could do a job at six. There has been a lot of negative media about him, people have never been certain about Chris Robshaw and I think he is paying the price for that.
"I personally think Tipuric is a little lucky to go. He is a headline number seven, he does some great things and in time he is going to be wonderful, but is he really that much better than Chris Robshaw over the ball? Does he have that experience? I think the answer is no on both of those counts and Robshaw is unlucky to miss out."
The tour gets underway on June 1.