Arsenal will always hope to win games at home but manager Mikel Arteta is unlikely to be too unhappy with this point against United.
The Spaniard suffered a couple of significant injury blows before kick-off when Bukayo Saka and Kieran Tierney were ruled out, adding to the absence of leading striker Pierre-Emerick Aubameyang, who was missing for personal reasons.
Arsenal’s reshuffled side acquitted itself well, although they were breathing a heavy sigh of relief when Cavani missed two openings that such an accomplished marksman might be expected to convert.
Arteta’s players have responded well to last Saturday’s bitterly disappointing FA Cup fourth-round loss at Southampton with a league victory away at Saints followed by this hard-earned point against United.
The Gunners went close to making it two victories since that exit, with Lacazette’s free-kick bouncing to safety off the woodwork with De Gea motionless – although that would have been harsh on United.
Arteta, constantly cajoling from his technical area, has a side that is very much a work in progress but their endeavour here – especially given the absence of key players – demonstrated he has something to build on.