It is Arsene Wenger's 1,161st game in charge of Arsenal. Increasingly, however, the question is not how many matches he has managed, but how many he has left.
Lose to Lincoln and it would be inconceivable he would remain in charge next season. It would also rank as the greatest shock in the FA Cup's 146-year existence.
Win, however, and Wenger would remain on course to become the competition's nonpareil. He has won it six times, as did George Ramsay, the secretary-manager of Aston Villa for 42 years.
Under other circumstances, a seventh victory would be celebrated. Now it would prompt questions if Arsenal were merely repeating campaigns that bring glory in neither the Premier League nor the Champions League. A number of Gunners fans would prefer this season had no silver lining if failure brings change.
After Bayern Munich's second 5-1 win over Arsenal in three weeks and five losses in seven games, the mood at the Emirates Stadium could be poisonous today.
That may suit Lincoln. Every minute they preserve parity will make the natives more restless.
The National League leaders should defend in numbers and concentrate on set-pieces, a game plan that worked perfectly when they beat Burnley in the last 16.
By way of comparison, Arsenal required controversial stoppage-time goals for both of their wins over the Clarets this season.
Similar in that respect, they are opposites in others. Arsenal go from facing perhaps the best team in Europe to, according to the standings, the 93rd best in England. Wenger's opponent on Tuesday was Carlo Ancelotti, a five-time European Cup/Champions League winner as player and manager. Now it is Danny Cowley, a physical education teacher last year.
Arsenal v Lincoln: Key battles
LAURENT KOSCIELNY V MATT RHEAD
Koscielny's importance was shown as Arsenal collapsed after his unfortunate sending-off against Bayern Munich. The Gunners captain is part of the new breed of centre-backs, slim and quick. Rhead, who used to build excavators, is an old-fashioned striker - a huge figure weighing 101kg- who presents a physical challenge.
KIERAN GIBBS V NATHAN ARNOLD
Arnold is a part-time barber and Lincoln had to resort to crowdfunding to be able to sign him. The quick winger scored a spectacular third-round winner against Championship side Ipswich. Wenger may choose to match pace with pace and bring in Gibbs to halt a man who has not played in the Football League since 2008.
ALEXIS SANCHEZ V LUKE WATERFALL
Waterfall set up his fellow centre-back Sean Raggett's winner at Turf Moor but the captain impressed even more as Lincoln's defensive rock. Sanchez's surprise omission at Anfield seemed to pave the way for his departure, but Waterfall has never faced a forward of his calibre. Wenger has to decide if he can do without the Chilean.
The Lincoln manager estimates they have a 0.1 per cent chance of victory. And, while Arsenal conceded five goals in a 31-minute capitulation to Bayern and are in their worst run of the season, they are actually remarkably immune to FA Cup shocks. Only one of their recent defeats, versus Watford, was to an underdog. They have a solitary FA Cup exit to lower-league opponents, Championship side Blackburn, under Wenger.
But the Frenchman can take no chances. He has to field a strong side. It will be intriguing if that includes Alexis Sanchez, whose future seems to lie elsewhere, and Mesut Ozil, scarcely a player to rally the side in tough times.
With talk of dressing room unrest, he ought to select the characters he trusts to avert embarrassment.
Arsenal showed their professionalism to see off non-league Sutton last month but have suffered perhaps the FA Cup's two greatest upsets, losing in 1933 to Walsall and 1992 to Wrexham. Now Lincoln may prove their spiritual heirs.
The non-leaguers will make £1 million (S$1.73 million) today. Money matters but, for both clubs, this is about history, about a place in it and those consigned to it.
ARSENAL V LINCOLN
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