Tsolekile’s fifth first-class hundred came against the Warriors in October 2009, but he finally cracked a sixth to help the Lions close day two on 311 for seven in response to the Knights’ total of 267.
The timing was excellent given that the Lions lost their overnight batsmen, Rassie van der Dussen and Dominic Hendricks, to Dillon du Preez inside the first hour of the day to sink to 68 for four.
Tsolekile joined Quinton de Kock at the crease, and the pair added a vital 70, with De Kock characteristically attacking while Tsolekile played the more cautious role.
Du Preez struck again when he had De Kock caught behind for 52 - the third time in three innings this season that De Kock has reached fifty and then got out - but Tsolekile found support from Brett Pelser (31) and then Hardus Viljoen.
Crucially, he saw off the second new ball, which arrived with the Lions on 227 for six and by no means guaranteed of a first-innings lead.
By the time Tsolekile was run out by Quinton Friend, the Lions were in front on 299 for seven and the second new ball had largely lost its shine.
Viljoen batted through to stumps for his 42, while Aaron Phangiso was unbeaten on five.
Du Preez had the pick of the bowling figures, with 3 for 35 from his 17 overs.