Preston North End twice came from behind to earn a late point against Bristol City, thanks to a second half brace from Emil Riis.
The visitors had taken the lead inside 12 minutes through Chris Martin, before Riis drew the Lilywhites level in the second half with his 15th goal of the season in all competitions.
Semenyo threatened to spoil North End's afternoon as he fired home at the near post ten minutes from time, but Riis had the last say with an extraordinary volley into the far corner in the last of five added minutes at Deepdale - that his 16th strike in all competitions this term.
Following his goal against West Brom in midweek, Cameron Archer came in to make his first start for the club in North End’s only change to their starting XI.
The visitors were the side on top in the game’s early stages and they had their reward 12 minutes in, with Weimann sliding the ball through to Martin, who sent an effort across Daniel Iversen to find the bottom corner.
His strike partner Semenyo came close shortly after as he volleyed over the crossbar from the edge of the box during a good spell of pressure from the Robins.
Later in the half, Semenyo did well to beat Browne to get to the byline, before creating the best opportunity of the half, finding top scorer Weimann free just more than six yards out, but he somehow sent his effort wide.
With the Robins a goal to the good at the break, Ryan Lowe opted to make two changes, as Josh Earl and Ali McCann entered the fray in place of Greg Cunningham and Ryan Ledson.
It took just seven minutes for North End to find their equaliser, with Archer seeing his long-range effort parried by goalkeeper Max O’Leary and there was Riis to send home the rebound.
The visitors looked set to take all three points when they retook the lead late on, as Han-Noah Massengo slid Semenyo through in to the left channel and he beat Iversen at his near post to put the Robins ahead with little time remaining.
But North End kept on fighting, as an Ali McCann recovery tackle on the edge of his own box crucially set up one final attack, which saw Potts deliver a cross from the right flank to find Riis in the middle, and the Dane hit a superb acrobatic volley into the bottom corner to claim a dramatic point for the Lilywhites.
PNE line-up: Iversen; van den Berg, Bauer, Hughes; Potts, Whiteman, Browne, Ledson, Cunningham; Riis, Archer (Evans, 79). Subs not used: Ripley, Lindsay, Rafferty, Sinclair.
Bristol City line-up: O’Leary; Kalas, Klose, Pring; Dasilva (Cundy, 82), Massengo, Scott (Vyner, 84), O’Dowda (Williams, 64); Martin, Weimann, Semenyo. Subs not used: Bentley, Wells, Conway, Benarous.
Attendance: 11,936 (523 away fans)
Referee: Mr J Busby