Horsey, 22, from Styal won the first stage at St Annes Old Links the week after turning professional following his Walker Cup appearance in September and has left himself with some catching-up to do in over the next three rounds.
His former England and Cheshire team-mate Paul Waring was well down the field after a 76.
Ellesmere assistant Martyn Hamer returned a 73 at Catalunya, seven off the pace, with Swinton Park's David Smith struggling on 77.
Didsbury's Danny Wardrop fired level-par 72 at Sherry Jerez to lie 20th and Stockport amateur Jamie Howarth, whose professional brother Scott is caddying for him, dropped two shots in a 74 at Costa Ballena for a share of 49th place.
Some 25 per cent of players from each course qualify for the final school in Spa.
KAREN Stupples' short season ends this week when she joins Scot Catriona Matthew as the only two British players in the £475,000 Mitchell Company Tournament of Champions in Mobile, Alabama.
Stupples, the 2004 Women's British Open Champion, gave birth to her first child Logan in April and the Kent golfer has played only six tournaments this year.
This event is for winners over the past four years and world No 1 Lorena Ochoa defends the title she won by 10 shots last year.
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