Lane shot 67 and Clark 68 to finish on 134, one shot behind the joint leaders Ronan Rafferty and America's Peter Teravainen.
It was a bad day for Sweden's Per-Ulrik Johansson, the defending champion and currently seventh in the Ryder Cup points table. He shot 76, missed the cut by five and could find several of his nearest Cup challengers overtaking him on Sunday.
Clark, 41 next week, made the last of his five Cup appearances in 1989 and knows he needs a do-or-die effort before Bernard Gallacher announces his team in 10 days' time.
After yesterday's round Clark said: "I need another pounds 100,000 to make the team but I would rather win here to get in easily than scrape in."
David Gilford, Mark James and Philip Walton, who are all in the top 10 in the Cup points table, safely qualified for the last two rounds. A good finish could make their spots secure.
The Ryder Cup has rather overshadowed the event but Rafferty and Teravainen are concentrating on the first prize. Rafferty would have led outright had he not hit his second shot into a bush at the long 17th and had to take a penalty drop.
The Welshman Mark Litton, who is only concerned with saving his Tour card, broke the course record with an eight-birdie 64.Reuse content