Sherman, who's using his father for his caddie this week, has failed to qualify via the Qualifying Tournament on four previous occasions.
Sherman, 28, is one of 168 players vying for his 2001 European Tour card. The top 35 and ties will secure their playing privileges for next season.
Two courses are in rotation for the six-day event, the second being Sotogrande, where England's Paul Streeter shot the low round of the day, a 5-under-par 67.
Other notables in the field include Sweden's Michael Jonzon, who shot 70, former Ryder Cuppers Phillip Walton and Steven Richardson, who each shot 73, and Justin Rose, who opened in 74. All four men played at Sotogrande. On the San Roque course, South African Desvonde Botes carded a 68, while Englishman Stuart Cage shot 70.
Last year, Roger Chapman, Niclas Fasth, Ian Poulter and Fredrik Jacobsen graduated from the Tour School. Chapman (Brazil Rio de Janeiro 500 Years Open), Fasth (Madeira Island Open) and Poulter (Italian Open) each won on the 2000 European Tour. Poulter also won the Sir Henry Cotton Rookie of the Year Award. Jacobsen finished 25th on the Volvo Order of Merit, the highest finish of the 1999 graduating class.