The four-time major winner, 30, replaces American Brooks Koepka.

Neither player featured at the Pebble Beach Pro-Am this weekend but the two-year rolling format of the ranking system takes McIlroy top.

This will be his 96th cumulative week as world number one - the fourth most of any player - but his first since September 2015.

Only Tiger Woods (683), Greg Norman (331) and Nick Faldo (97) have spent more weeks as the world's top-ranked player.

The complicated nature of the ranking system takes McIlroy from 0.2 points behind Koepka to 0.03 points in front.

Both players are scheduled to play at the Genesis Invitational in California, which begins on Thursday.