With Belize long since eliminated, the door is open for another to knock McCaulay off his perch.
Four-time Ballon d'Or winner Messi and compatriot Gonzalo Higuain - who have 10 and nine goals, respectively - would have been expected to leapfrog McCaulay in Argentina's final two games but injuries have seen them pull out of the already-qualified Albiceleste squad.
Antigua & Barbuda ace Peter Byers is another well-placed player who has no longer has any chance of adding to his tally of 10 goals, with his country's hopes of qualification having ended in the third round of the CONCACAF qualification campaign.
USA striker Clint Dempsey, on eight goals, must also watch from the sidelines with his nation having already sealed its spot in Brazil. However, Panama veteran Blas Perez could become a national hero by helping his country qualify for the first time, with the added incentive of individual glory if he sufficiently improves upon his impressive 10-goal haul.
Uruguay cannot afford to lose either of its final ties if the team wants to qualify for the World Cup, meaning Suarez's goalscoring ability will be much needed this month, as he looks to increase his tally of 10 goals. Radamel Falcao, meanwhile, has seven goals to his name and can fire Colombia to the 32-team finals with a win in the country's penultimate clash at home to Chile.
In Europe, Van Persie has helped book Netherlands' ticket to Brazil with his eight goals, but more weight rests on Dzeko's (also on eight goals) shoulders, with Bosnia & Herzegovina neck-and-neck with Greece in the race for automatic qualification.
However, it would be a huge shock if seven-goal Jordan attackers Hassan Abdel-Fattah and Ahmad Hayel added at least four goals to their respective totals in their playoff with the fifth-placed CONMEBOL qualifier.
New Zealand's Chris Wood could top Oceania's goalscorers' chart outright - ahead of New Caledonia's Georges Gope-Fenepej - with at least two goals in his nation's playoff with CONCACAF's fourth-place finisher in the region's fourth round of qualification.
No player in CAF qualification has scored over six goals, meaning the top scorer is most likely to come from the Americas, with UEFA, AFC and OFC providing outsiders in what is still a very competitive race.