But in the end, City will be extremely pleased to have earned one point as they trailed 3-2 going into stoppage time.
Ryan Sharman gave the visitors an early 9th minute lead that Jahson Downes cancelled out in the 26th minute.
Sharman doubled his and City`s tally to restore their advantage just before half-time, only for former City player Allen Bossman on 70 minutes and Jordan Brown 12 minutes later to put Marlow 3-1 ahead.
But City had a 90th minute penalty to thank for rescuing a game after he had been brought down – the striker picking himself up to complete his hat-trick and a secure point for his side.
AFC Rushden & Diamonds are now third and just a point behind Cambridge after a more comprehensive 4-1 win at Honeycroft against Uxbridge.
Recent signing Ryan Robbins put Diamonds in front after 10 minutes and a Tom Lorraine brace in the 20th and then right on half-time took the visitors three-up at the break.
Left-back Sam Brown added a fourth for the Northamptonshire outfit on 67 minutes – and they even scored the Reds` consolation when the unfortunate Callum Westwood beat his own keeper in stoppage time.
Hayes & Yeading United maintained their steady climb up the table and are now fifth after recording a 2-1 home win over bottom-markers Arlesey Town.
Toby Little proved to be the home side`s hero, bagging a brace in the 19th and 26th minutes and surviving a comeback when Tony Williams reduced the deficit after 65 minutes.
AFC Dunstable dropped to seventh after losing 1-0 at mid-table Chalfont St Peter.
Ben Ward-Cochrane`s 66th minute effort eventually proved enough for the Saints.
Fleet Town pulled five points clear of Arlesey in third-bottom spot after a 2-0 Calthorpe Park victory over Aylesbury FC.
After a goalless opening 45 minutes, Matt Bunyan broke the deadlock to give Fleet a 56th minute lead that Luke Haskell doubled 12 minutes from time.
Barton Rovers are level on points with Fleet but one place better off after sharing a 1-1 Sharpenhoe Road draw with a Northwood outfit who are now eleventh.
The Woods led through Jermaine Osei`s goal immediately after half-time until 6 minutes from time when Rovers levelled from the penalty spot, converted by Danny Watson.
Kempston Rovers and Egham Town are tenth and ninth respectively after they shared a 2-2 Hillgrounds draw.
A fine Ben Shepherd free-kick from 25 yards gave the Walnut Boys a 16th minute lead that Robbie Goodman doubled after 34 minutes.
But the Sarnies fought back with a brace of goals from Brendan Matthew after 52 minutes and a penalty given for a shove by Jermaine Ivy 15 minutes from time.
Ny Steve Whitney
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