Durban - Dwaine Pretorius' second five-wicket haul in first-class cricket moved the Lions a step closer to the Sunfoil Series title as they took firm control of their encounter with the Dolphins on day two at Sahara Stadium Kingsmead.
Pretorius outshone his more illustrious fast-bowling teammates with two telling spells, which yielded figures of 5 for 34 in 17 overs and reduced the Dolphins to 229 for eight.
The hosts, therefore, went to stumps trailing by 166 runs with just two wickets in hand, having bowled the Lions out for 395 in the first part of the day.
The Lions resumed on 280 for five, and the morning session made for entertaining viewing as the runs flowed even as wickets fell.
Temba Bavuma converted his overnight 124 into 153 before he was caught behind off the bowling of Matthew Pillans (3 for 90), while Chris Morris gave the innings a boost by scoring 57 from just 70 deliveries.
Daryn Dupavillon claimed two wickets in the morning session to finish with 4 for 72, while Morris was the last man out when he was bowled by Daryn Smit.
The Dolphins made an aggressive start to their reply, taking 47 off the first eight overs, but the approach caught up with them over time.
Imraan Khan was run out after a run-a-ball 27, and when Daniel Sincuba edged Pretorius to first slip to fall for 56 from just 68 balls, the hosts found themselves 100 for four in the 24th over.
That soon became 101 for five when Khaya Zondo missed a straight one from Pretorius, whose seven-over spell before tea brought him 3 for 6.
The Dolphins kept him wicketless for five overs after the interval as Morne van Wyk and Smit rebuilt the innings, but Pretorius returned to break the 116-run stand by trapping Van Wyk lbw for 68.
Smit battled through to stumps to remain unbeaten on 49, but lost two more partners to leave the Dolphins in need of a mammoth turnaround to keep their trophy hopes alive.
Sapa