"We all want to see better players coming in. We are playing in Europe and we know it is going to be a tough season."
Despite injuries to Tim Cahill and James Vaughan, Yobo insists he isn't worried about the fast-approaching start to the Premier League season.
"Our squad is not the biggest and we have got a few injuries, to Vaughany and Tim," he said.
"But they will recover before too long and who knows what will happen before the start of the season?
"If we can sign one or two quality players, that would be great."