Joshua has jumped at the chance to rematch Ruiz since the colossal upset in June, hoping to adjust his game plan and prove his class.
But Froch believes Joshua must raise his level and deliver a display better than anything produced previously.
“Hopefully he can pull out a career-best performance, because I think he’s going to need it,” Froch said in his Sky Sports column.
“We all want to see him really perform, keep his mind focused, stick to a game-plan and pull off the win. A knockout like Lennox Lewis did against Hasim Rahman would be the ultimate comeback, and just sets the record straight. It would be ideal.
“We have seen what he needs to do to win. He can box and move and when he landed that left hook he put Ruiz Jr over, but the problem he’s got is that Ruiz Jr now has grown massively in confidence. He’s started to believe in himself. Instead of going into the ring thinking ‘Can I do it?’ He now knows he can do it.”
Meanwhile, Eddie Hearn has also moved to dismiss speculation that Joshua was hurt during sparring in the build-up to the rematch.
“It (the story) said, ‘Joshua hurt in camp,’ it’s not even worth answering. But the truth is he’s had a great camp,” Hearn told Behind The Gloves.
“He’s much more focused than last time. He’s sparred really well.”
“He’s much more focused than last time. He’s sparred really well.
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