Catt, who has not played since returning from Australia after England's World Cup triumph in November 2003, had a mixed first half, but his second-half showing suggests that he could still figure in his country's RBS Six Nations campaign this season.
The England veteran was unable to get onto the scoreboard, with fullback Chris Malone, who kicked 17 of his side's 22 points, also proving a valuable man for the home side.
Malone put his side on the scoreboard in the ninth minute with a well-struck penalty, but Leeds back rower Dan Hyde put his side ahead with a try after brushing off some Bath defenders close to the line.
Leeds's Scotland fly-half Gordon Ross converted Hyde's score to give his side a 7-3 lead, but two more Malone penalties put the home team ahead by 9-7 – only for Ross to slot a drop-goal for a 10-9 half-time lead.
Ross extended that one-point lead to four points with a penalty in the first minute of the second half, but Bath managed to stay in touch, with the wind at their backs, and when back rower Isaac Fea'unati got over in the 63rd minute – after a Malone penalty in the 50th minute – Bath had suddenly established a 19-13 lead.
That six-point lead, however, soon became a nine-point lead as Malone knocked over his fifth penalty goal – denying the visitors a bonus point for losing by seven points or less.
For Bath:Try: Fea'unatiCon: MalonePens: Malone 5
For Leeds Tykes:Try: HydeCon: RossPen: RossDG: Ross