Lancashire arrived at Taunton on 15 July 1895 to face a moderate Somerset attack on a benign pitch. MacLaren, then 23 and Lancashire's amateur middle-order man, opened the innings and was at the crease for 470 minutes, hitting a six and 62 fours. He passed W. G. Grace's 344 (made for MCC v Kent in 1876) shortly before lunch on the second day, the previous record for the highest individual first-class innings. He was eventually dismissed for 424, caught in the deep.
MacLaren's 424 stood as the highest individual first-class innings until Bill Ponsford's 429 for Victoria in 1923 and the highest in English first-class cricket until Brian Lara's 501 not out for Warwickshire in 1994. It is still the highest individual innings ever made for Lancashire and the highest in a County Championship match.
The Taunton 424 made MacLaren the most marketable English amateur of his generation. He captained Lancashire from 1894 to 1907 (with brief interruptions) and led England in 22 of his 35 Tests between 1898 and 1909, taking sides to Australia in 1897-98, 1901-02 and 1909, and captaining at home in 1899, 1902 and 1909 Ashes Tests. As an opening batsman of grand-manner technique he made 47 first-class centuries and 22,236 first-class runs at 34.15.