The 31-year-old American, who pulled off one of Wimbledon's biggest-ever shocks in beating Steffi Graf in the first round last year, summarily dismissed Belgian teenager Laurence Courtois 6-0, 6-3.
On the evidence of this, she will again be one of the opponents to be avoided by the leading players in the early rounds at the All-England club later this month.
McNeil has yet to drop a set this week and her young rival managed to take only seven points in an embarrassingly one-sided opening set. Courtois, seeded 11 and the first-round conqueror of Britain's top women's player Clare Wood, made a brave effort in the second set after breaking McNeil's serve in the opening game.
"When I play well like that it doesn't matter if my opponent only misses a few shots," the Texan said. "After the first set, it was obvious the second was going to be a bit tougher, but I was pleased with my form again."
McNeil, who finally went out at Wimbledon last year to the eventual champion, Conchita Martinez, in a tight semi-final, takes on the South African, Elna Reinach, today for a place in the Birmingham final, which carries a pounds 16,000 first prize.
Reinach, seeded 10, started and finished powerfully to beat Nicole Arendt, of France, in three sets.
The other semi-final will be between No 3 seed Zina Garrison Jackson and last week's Beckenham winner Els Callens.
The unseeded Callens, another Belgian challenger, again showed the value of intensive grass-court preparation with a sharp win in straight sets over Australia's Kristine Radford.
Garrison Jackson, the 1990 champion but well beaten in the final by McNeil last year, maintained her chance of a revenge-meeting with a comfortable 6-2, 6-3 victory over Germany's Christina Singer.Reuse content