Judd Trump begins Masters title defence with win over Kyren Wilson
The defending champion looked down and out early on, but he battled back with some impressive breaks, including a 101, to level the score at 3-3.
The match went down to the wire, with both players trading frames before world number two Trump eventually sealed the victory with a 65 clearance in the decider.
"It was a strange game - nip and tuck the whole way through," Trump told BBC Sport.
"I was just fighting not to go 4-0 down.
"At 5-4, Kyren made an unbelievable clearance to go 5-5.
"I felt quite nervy out there from the start. I couldn't even chalk my cue at one point. In that last break I was on my way home and he took a little bit of a risk and was unfortunate to leave the gap.
"You would think with my experience you would get over the nerves but coming here, to the World Championship or the UK is a different feeling, you just don't want to go out in the first round."
Wilson was disappointed to lose, but he admitted that Trump deserved the victory.
"I should have hit home a little more at 3-0," Wilson said.
"I am disappointed not to finish it off. I should have. That is how my season has gone. All year it has been exactly the same.
"I just can't believe I have left the red through the gap and it sums up my season - but every credit to Judd."
Trump's win sets up a quarter-final clash with Ali Carter.
Barry Hawkins defeated Neil Robertson 6-3 in Tuesday's evening session and will face Ronnie O'Sullivan in the next round.
The Masters continues on Wednesday with Mark Selby taking on Jack Lisowski and Mark Allen facing John Higgins.