The Rocks summoned up a late equaliser for the third game in a row to claim a Bostik premier point at Leatherhead.
They trailed 2-1 going into the third minute of injury time - as they had in the FA Trophy at Bracknell. But for the second Saturday in a row the young striker on loan from Pompey came to the rescue with a superb finish to make it 2-2.
The Rocks also needed a late equaliser in midweek - that one from Jimmy Wild - as they recovered from 2-0 down in the Bracknell replay at Nyewood Lane to take the game to extra-time before winning on penalties.
At Fetcham Grove today, Shaun Okojie gave the Tanners a 17th-minute lead before Tommy Scutt levelled on 56 minutes.
Ibrahim Olutade restored the hosts' lead 11 minutes later and that looked to be enough for the win until Lethbridge netted his ninth goal of the season.
The draw sees the Rocks fall to sixth place, but they will take heart from the fact they have lost only one league game.
Tonbridge are top, six points in front of Jack Pearce and Robbie Blake's men.
Elsewhere Pagham are the area's last remaining team in the FA Vase following a 4-1 home win over Peacehaven. Chichester City won't be enjoying their third successive fine run in the competition this season, though - they lost 2-0 at home to Windsor.
In division one of the Southern Combination Daren Pearce's Selsey romped to a 7-0 win at home to Oakwood. Brad Higgins-Pearce, Lindon Miller, Tom Atkinson and Remi Coates with a hat-trick were the goal heroes and one was an own goal.
Midhurst went down 4-1 at home to Seaford.
In the Division 2 Challenge Cup, Bosham found Brighton Electricity had too much power, the visitors winning 2-1 at Walton Lane to knock out the holders.
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