In 1889, Millwall Rovers changed their name to Millwall Athletic and in 1892, the original Barnet FC met Millwall Athletic in the semi-final of the Middlesex Junior Cup with the South London side winning 3-2. Barnet's goals coming from Dresser and Parsonage.
In the 1899/00 season, the two clubs met again in the London League Division One and Millwall completed a double winning 1-0 at Millwall's Athletic Ground and 2-1 at Queens Road. The following season, Millwall won 6-0 and 7-0 and the latter match in January 1901 proved to be something of a watershed for the club as they withdrew from the London League after that game and never really recovered, going into liquidation a year later.
In 1907/08, Barnet Alston and Millwall met in the London League Premier Division drawing 1-1 at Millwall's ground in North Greenwich with Pat Galienne scoring for the Amber & Blacks . In the return at Alston's new Underhill ground, Barnet & Alston defeated Millwall 3-0; Teddy Harrison, Galienne and Reynolds scoring for Alston.
The following season, 1908/09, Millwall completed the double over Barnet winning 4-1 at Millwall, Seabrook scoring for Barnet and 2-1 at Underhill, Purvis getting the Alston goal. In 1909/10, Alston won 4-3 at Millwall with goals from Ridley, Gallienne, Seabrook & Aylott. Barnet Alston completed a league double over the Lions winning 2-0 at Underhill later that season.
The two clubs were not to meet for nearly another century. It wasn't until 2009/10 when Barnet defeated Millwall, who were then, as now, a League One club, at Underhill in the 1st round of the Johnstones Paint Trophy. Barnet won 2-0 with goals from Jake Hyde and Ismail Yakubu.
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