In the 50th minute Perry was brought off for Thomas, who had been sin-binned within two minutes of coming on, and Bath took full advantage of the extra man by scoring two converted tries.
Meanwhile, Sally Gunnell, John Regis, Suzi Perry and Blue Peter's Simon Thomas will be on the streets, talking to some of the "fun" runners, many of whom raise huge amounts of money for charity - a major part of the success of the marathon.