Again the defensive part of their game was more effective than at the other end of the pitch.
Johnny Mullins was outstanding, but United also owed a debt to goalkeeper Ryan Clarke, who denied Arron Davies early on and Danny Coles at the death to preserve a fourth successive clean sheet.
The visitors threatened in the opening 20 minutes, but once more felt the absence of Dave Kitson as they struggled to carve out chances.
- Michael Raynes challenges Artur Krysiak
Lewis promised he would not make major changes and his first team sheet was true to his word.
Injuries ruled out Jake Wright and Ryan Williams, so Michael Raynes and Sean Rigg came in as the U's stayed with a 4-4-2 formation.
Pre-match fears over the pitch were unfounded, but the surface was very heavy.
Neither side had problems to begin with in an entertaining opening.
The home side were the first to show and almost took the lead in spectacular fashion on nine minutes.
Out of nothing Davies let fly with a 25-yard dipping volley which Clarke tipped on to the crossbar.
The midfielder was clearly in the mood, as within a minute he fired a scissor kick into the away fans.
It stirred United, who went on to have a good spell.
- Deane Smalley just misses out as Exeter goalkeeper Artur Krysiak comes quickly off his line
Deane Smalley was denied by goalkeeper Artur Krysiak, who also tipped a shot from Nicky Wroe round the post. From the resulting corner he was in the right place to hold on to Tom Newey's header.
United's momentum was slowed by an injury to Danny Rose, who had to leave the field with a cut on his head.
The midfielder ran down the tunnel to receive treatment and the visitors had to play for seven minutes with ten men before he returned.
Unfortunately they were unable to find the higher gear again and the game drifted in the final 20 minutes of the half.
Michael Raynes was forced off at half time, forcing a reshuffle in United's back four.
David Hunt shifted to centre back, with Matt Bevans coming on at right back.
City started the half brightly and opened up United to send Davies through. He rounded Clarke, but was forced wide and although he centred the ball an Exeter teammate could not get on the end of it and United scrambled clear.
It was a rare chance as the game quickly settled back into a stalemate.
Both sides struggled for ideas in the final third. The uneven, muddy surface did not help matters, but there was still a real lack of quality, particularly from wide areas.
Rigg was played on the right flank all night without any joy, while on the other side Josh Ruffels lacked the pace or trickery to cause problems.
Exeter had more of the pressure, but once again the defensive part of United's game was in good working order.
Clarke took the sting out of several dangerous moments with good decision-making.
He earned a point in stoppage time with a brilliant stop to keep out a firm header from Coles in stoppage time.
- Highlights from Oxford United's draw
Oxford Utd (4-4-2): Clarke, Hunt, Raynes, Mullins, Newey, Rigg, Wroe, Rose, Ruffels, Smalley, Constable.
Subs used: Bevans (Raynes ht), Davies (Rigg 90).
Unused subs: Henly, Long, Lynn, O'Dowda, Marsh.
Exeter (4-4-1-1): Krysiak; Butterfield, Baldwin (Gow 73), Coles, Woodman, Sercombe, Gill (Grimes 58), Bennett, Davies, Keohane, Nicholls.
Unused subs: Pym, Oakley, Moore-Taylor, Parkin, Jay.
Attendance: 2,798 (218 visitors).
Referee: Christopher Sarginson (Staffordshire).