The 34-year-old succumbed to a close-fought, 4-3 defeat at the hands of Cypriot Michael Georgiou, but was left ruing a series of match-winning chances at various stages of the encounter.
Georgiou took the first frame 63-51, but Grace hit back with a break of 61 to edge the second and level the tie, before making it 2-1.
After his rival made honours even again, the world number 94 took the fifth before missing a crucial pink that Grace believes turned the game in his opponent’s favour.
Georgiou went on to make impressive breaks of 97 and 80 to see the game off, and Grace acknowledged he simply didn’t do enough to earn progression to the last 64.
“I didn’t play great, to be honest,” he said. “It was a bit scrappy and I could never press ahead when I got in front.
“He’s a strong player and I know his game well. He showed his class in the last two frames with two good breaks, but I had opportunities to win as well.
“There were points when I was missing shots that I should be able to make with my eyes closed, but unfortunately I wasn’t able to do that. Unfortunately, I just wasn’t good enough on the day.”
With the snooker season only just beginning to move into top gear, Grace admitted he has struggled to gauge the level at which he is currently at but explained he will hit the practice table hard ahead of a hectic winter period.
He said: “The campaign has been very stop-start up until now and there hasn’t been a long run of matches. It’s just been a case of going into tournaments and hoping to find a bit of form every time.
“We’ve got a few tournaments between now and Christmas, so I’ll just have to keep practicing ahead of the big tournaments like the UK Championship which will come around sooner rather than later.
“There aren’t certain things I think I need to work on, I just need to get my head down and keep going.”
Elsewhere, Rotherham’s Ashley Carty also tasted defeat in his opener, falling 4-0 at the hands of Elliot Slessor.
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