Fifteen-time world champion Phil Taylor has crashed out of the PDC World Championship in the second round, losing 4-1 to Dave Chisnall.
Taylor, from Stoke, looked out of sorts from the opening leg and was brushed aside by his St Helens-based opponent.
"Dave was the better player," a gracious Taylor told Sky Sports 1.
"When he took that fourth set it was a massive blow for me, then I was struggling. It's all on the night and I wasn't good enough."
A stunned Chisnall admitted: "I don't know how I did that.
"I threw well in the game but started getting a bit nervous at the end. When he gave me a chance I took it.
"I've always thought I can beat anybody if I play my game. I thought I could beat him when I came into the championship."
Taylor twice won the BDO version of the world title before switching to the rival PDC, where he has won the title 13 times, the last coming in 2010.
He revealed he had been handicapped by faltering eyesight and was affected by the heat on Tuesday night, but insisted: "I'm not going to knock my performance; I'm not going to knock Dave's performance. I thought he was the better player.
"I'm going to do another two or three years and then I'm going to retire."
Both players missed important throws at Alexandra Palace and, although Chisnall gave a glimpse of what was to come when he took the first set, Taylor hit straight back to win the next.
The next two sets went to Chisnall to set up the chance to cause the upset of the tournament.
After taking the opening leg of the fifth set Chisnall was pegged back but he won the next two legs, including a stuttering finish in the final leg.
He finally hit double six, after Taylor had missed two shots at double 20, to win the set 3-1 and stun the world of darts.
PDC WORLD CHAMPIONSHIP - RECENT WINNERS
2011: Adrian Lewis
2010: Phil Taylor
2009: Phil Taylor
2008: John Part
2007: Raymond van Barneveld
2006: Phil Taylor
2005: Phil Taylor