[3] After the end of his rugby career, Nicholls became a publican and in 1894 he acquired a business interest in the Grand Hotel, opposite the Cardiff Arms Park.
"Keenor was officially listed at a meeting of club directors at The Corporation pub in Canton on 19 January 1927.
At the summit, called by Sid Nicholls, fellow board member Walter Riden – Keenor's old teacher at Stacey Road Primary School in Adamsdown – proposed listing the captain.
But within weeks the captain won his place back, his name was removed from the list and on 23 April he led the Bluebirds to their most famous victory, a 1–0 win over Arsenal.".
[9] Around 1920, Nicholls had met Katherine Brennan and went on to have a second family with her consisting of five sons and one daughter out of wedlock, scandalous for the time.
Nicholls was first selected to represent Wales in 1888, in the first match between the country and Southern Hemisphere opposition, the New Zealand Natives.
Under the captaincy of Frank Hill, Wales were beaten by two tries to nil, though selectors kept faith with Nicholls when he was chosen for the final game of the tournament to Ireland.
The Scottish outplayed Wales scoring seven tries without reply, with the Welsh team hamstrung by an inefficient pair of halves.