Knowing that Oldcorn had set the clubhouse target of 205, courtesy of an 11-birdie round, Brand notched six of his own, against two bogeys, to reach 12 under and seal a one-stroke victory.
"It's great, because I've been playing awful for the last year and a half," said 55-year-old Brand. "I haven't had a top-10 all season and my coach told me last week that I'm the best player on the range and the worst player on the course. Even after two 68s, I just wanted something to boost me forward, but I continued to play really well today, and I managed to do it despite Andy Oldcorn - or Bagpuss as we like to call him - giving us all a fright. I couldn't be happier. When you get in the mix it's great, but to finish it off is so satisfying.
"My best shot was the pitch to the 16th. I'd just made a poor bogey in the 15th, so it was the perfect way to bounce back. I knew it was tight coming down the stretch - I always like to look at leaderboards and be aware of what I need to do - and I was pretty tense hitting the approach into the 18th. It's a smelly shot over water against the breeze, so I was pleased to hit a good shot and two-putt.
Oldcorn hailed the best round of his career after threatening that elusive sub-60 score. He was 11 under through 15, narrowly missed birdie chances on the final three holes, but settled for the joint lowest round in the history of the Senior Tour.
"It's the best round of my career, which spans nearly 30 years," he said. "I've known in the last few weeks that a good score was coming, because I've been playing so well and putting so poorly. I didn't think it would be as low as that.
"I got a tip from my wife on the phone last night for my putting, funnily enough, and it worked - although I had two tap-in birdies on the front nine.
"I wanted to get to 12 under down the stretch, but I just couldn't do it. I had a really difficult lie with my third shot on the par-5 17th, and I honestly don't know how that putt for birdie at the last missed. It just died off to the left an inch from the hole.
"These days don't come along very often and I wanted to make the most of it. I'm glad I did that, even though it was one short. Congratulations to Gordon for finishing off the job."
Oldcorn was joined by Angel Franco (69) and David J Russell (67) in a tie for second place.