Volkov broke McEnroe in the first game and they went on to a tiebreaker in the first set.
"I was hoping for one chance and I got three," he added, referring to the three times he broke McEnroe.
He broke McEnroe twice in the second set while losing only one point on his own serve, then blasted five more winners in the last tiebreaker.
Lendl, in turn, broke McEnroe four times.
Mecir broke McEnroe in the third, fifth and seventh games of the fourth set, then held serve to capture the biggest title of his career.
Garrow, ranked 94th in the world, broke McEnroe in the opening game of the second set and held serve for a 2-0 lead.
Evernden, 24, broke McEnroe with three outright winners in the first game of the match.
In the 11th game, Mansdorf broke McEnroe, hitting crisp returns and angled volley winners.
Woodforde closed out the match, breaking McEnroe for the third time in the set, hitting a backhand return at McEnroe's feet.
It proved inconsequential after Lendl broke McEnroe back in the next game.