Luke Donald and Rory McIlroy compare notes at the Dubai World Championship in 2011 Kamran Jebreili/AP/Press Association Images

Number crunch: Rory needs a big two months to hold on to Number 1 spot

McIlroy was a summer-time bloomer in 2010 and 2011 and only a similar vein of form will stave off Luke Donald

THINGS WERE SO simple when Tiger Woods reigned as world number one in the golf rankings for 623 consecutive weeks.

Rory McIroy reclaimed top spot on Monday morning after Luke Donald could not finish in the top eight at the Heritage tournament in the United States.

With the golf rankings currently based on form over a two-year period, and both players enjoying winning summers in 2010 and 2011, expect the period of flux to continue.

Breathing space

The duel between McIlroy and Donald will be a largely exclusive one until the U.S Open at the Olympic Club in San Francisco in June. Fallow periods over the next two months, however, could see Lee Westwood  and possibly Bubba Watson in contention for the top spot.

At present, the Northern Ireland golfer sits on 470 (approx.) ranking points at an average of 9.59 points per tournament. His English rival has over 492 points but his average works out at 9.48 as he has played four tournaments more than McIlroy in the past two years.

The duo are entering a period of eight weeks when they can build on the success of previous years or fall back towards the chasing pack.

McIlroy’s next scheduled event is the Wells Fargo Championship, beginning on May 3. He won his first PGA tournament at the Quail Hollow course in 2010 and stands to lose up to 30 ranking points if he finishes well down the leaderboard or misses the cut.

Players Championship

Donald will not feature at Quail Hollow and will compete, instead, at the Zurich Classic of New Orleans; a tournament won by Masters champion Bubba Watson in 2011.

The Players Championship at Sawgrass follows and Donald will be looking to improve upon his fourth place finish last year.

McIlroy and Donald (with caddy John-Paul Fitzgerald) at the Ryder Cup in 2010. (Credit: Jon Super/AP/Press Association Images)

McIlroy missed the TPC last year but is a confirmed participant for the event that KJ Choi won in May 2011. 80 world ranking points are awarded to the winner.

Both players will play at the BMW PGA Championship at Wentworth, starting on May 24. Donald won the title last year, gaining 70 points in the process, while McIlroy finished in 24th position.

US Open

World number one and two will appear at the Memorial Tournament in Dublin, Ohio from May 31 to June 3. McIlroy holds the edge here as he finished fifth to Donalds seventh in 2011.

However, if the Holywood golfer wants to secure a place at the summit of world golf for the foreseeable future, retaining his U.S Open crown will confirm him as the world’s best golfer and deliver another 100 rankings points.

May and June have been fertile golfing periods for McIlroy and Donald and they will hope that the words of George Gershwin ring true – “Summertime, and the livin’s easy.”

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