It was the hosts (pictured on the attack by Mikey Cartwright) who came closest to breaking the deadlock when Kris Newby hit the woodwork in the second half.
Ramsgate won 2-0 at third-placed Hythe in Ryman South, lifting themselves from 14th to ninth in the table and within three points of a play-off spot. Dean Hill gave them the lead two minutes after the interval and Ian Pulman made sure near the end.
Leatherhead are up to seventh, a point ahead of Ramsgate, after their 1-0 home win over Herne Bay. The only goal came even earlier in the second half, with Tommy Hutchings the marksman for Tanners.
While losing the Premier leadership, Whitehawk advanced to the quarter-finals of the League Cup with a 2-0 home win over Maidstone, second in Ryman South. Paul Armstrong put Hawks ahead in the 40th minute and a last-gasp strike by Jed Wallace made sure.
Holders Bury are out, beaten 2-1 at Concord in their all-Premier clash. Danny Glozier scored for the Beachboys four minutes after half-time, with Craig Parker replying midway through the half. The winner came from Tony Stokes with seven minutes left.
Thurrock, in a way, are also defending the trophy. They won it in 2004 and this is their first season back in the competition after an eight-year stay in Conference South. They had goalkeeper Will Viner to thanks for two penalty shoot-out saves as they went through 6-5 after a 1-1 draw at home to Waltham Forest. Robbie Norris put Thurrock ahead on 18 minutes only for Joel Palmer to reply for the Ryman North side four minutes later.
Thamesmead also needed penalties to see off Ryman North rivals Aveley after a 2-2 draw. With both sides in the play-off places a tight battle looked likely and it was scoreless for 55 minutes. Then Jordan Cox put Millers ahead and Jay Leader made it 2-0 eight minutes later. Lea Dawson quickly reduced the arrears, Stuart Zanone levelled it on 74 minutes and Thamesmead capped their comeback with a 4-3 victory from the spot.
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