The Wanderers' pole position had been usurped briefly by Norwich City, winners of Friday night's East Anglian derby, but it took only seven minutes for the Canaries perch to appear precarious indeed. The striker Nathan Blake dummied Gerry Taggart's pass leaving the Danish international Michael Johansen to score at the far post.
Then it was McGinlay's show. He made it 2-0 13 minutes later and, seconds after Toddy Orlygsson had missed Oldham's best chance, Taggart's 30-yard pass picked out the Scottish striker and he finished calmly.
Third met fifth at Oakwell and the expected tight match between Barnsley and Crystal Palace finished goalless after the Londoners' England under- 21 goalkeeper Chris Day saved Neil Redfearn's second-half penalty.
Birmingham had not scored for six hours and 52 minutes but it took Paul Devlin only 39 seconds of the match against Bradford to break the spell. Barry Horne's long ball was deflected into his path and he hit a powerful, low shot across goalkeeper Eric Nixon, whose saves prevented a much heavier defeat. Devlin and Jonathan Hunt made it 3-0; Bradford, including the on-loan Chris Waddle, made little impression.
Elsewhere, Portsmouth won their first match in seven when goals by John Durnin and Lee Bradbury proved enough to beat Charlton at Fratton Park and Swindon won their first game in four. Kevin Horlock scored six minutes into the second half to beat Oxford.
In the Second Division, the final unbeaten record in the Nationwide fell when the leaders Brentford were beaten 2-0 at Crewe who moved up one place to fourth. Mark Rivers and Shaun Smith scored after a goalless first half. Bury go second despite having David Johnson sent off after 84 minutes of their 2-1 win at Peterborough. What can he have been so exercised about? A minute earlier he'd scored the Shakers' winner.
And congratulations to Bournemouth. At the sixth attempt, they won at home. The 2-1 win over Wycombe also gave the Cherries their first home points of the season.
Fulham went back to the top of the Third Division after a 3-1 win over Doncaster, Mike Conroy's goal taking his season's total to 10. The previous leaders, Carlisle, slipped to third after being held 2-2 at Rochdale, who remain one off the bottom, allowing Cambridge to coast into second spot following a 2-1 win at bottom club Brighton.