The Masters 2013: Tiger Woods under threat as chasing pack bare their teeth

You can almost smell those Georgia pines, leaking sweet perfume all over Augusta. The first major of the season, the Masters, is only a week away and the big dogs are starting to bite. Tiger Woods heads the list of most right-thinking golf fanciers trying to pick a winner. Three victories in four stroke-play events on the PGA Tour this year is all the evidence required to make the case for the re-instated world No 1. But, compelling as Woods is, he has yet to win at Augusta after coming into the event on the back of a hat-trick of tour titles, which is all the more reason to embrace the powerful arguments being made elsewhere.

Charl Schwartzel struggled to adjust to life in a green jacket after his dramatic Masters triumph in 2011. The rest of the year past in whirl of celebration and ceremony and it was almost a relief to step down as champion to rediscover his game. A rib injury last summer held him back. He started to find some form at the eight-man Turkish Airlines jolly in Turkey last October, and from there has not looked back. Six top-five finishes in his past eight stroke play events, including victory at the Alfred Dunhill Championship in South Africa are proof of that.

The last of Phil Mickelson's three Masters titles came three years ago, wrenching the crown from the grasp of Lee Westwood with arguably the finest escape seen at Augusta, the 6-iron between trees and off pine needles to four feet at the 13th. Mickelson boasts one victory this year, in Phoenix, where he opened with a 60, and he flickered ominously at Houston after reverting to his traditional putting grip. His four-birdie opening stanza on Sunday revealed once again that when he gets the ball rolling there are few as dangerous, especially this close to Augusta.

Where has Dustin Johnson been hiding since his victory at the season opener in Hawaii? Perhaps the question is irrelevant after his Sunday low score of the day 65 in Houston, which propelled him into fourth. With Johnson's length off the tee Augusta's wide open spaces are an obvious attraction but it was his improved iron play in Texas that made the difference and sets the heart racing at what might be in Georgia. Johnson has been searching for rhythm on the greens and, aided by the reliability of his approach play, found it on surfaces remarkably similar in pace and topography to the Masters.

Nestling inside the top 10 at Houston was Louis Oosthuizen, pipped in the play-off at last year's Masters by Bubba Watson's unfeasible wedge at the 10th. Oosthuizen vies with fellow South African Schwartzel for the award of most aesthetically pleasing swing. Unflappable under pressure, Oosthuizen needs only to unlock the putter to threaten. He closed out his final four tournaments of 2012 no lower than sixth and was a winner at the Volvo Champions in January. His form slipped thereafter but we saw enough signs in Houston, where he shot a bogey-free 65 on Saturday, to suggest he will not be far adrift at Augusta.

Justin Rose has spent the past week preparing at home in Florida. He chased Woods home last time out in Bay Hill and his rise to a career-high world No 3 suggests he is as close as any to a major breakthrough this year. Rose has the lowest scoring average on the PGA Tour this season, tops the sand saves stats and is better than any from 125 yards in. That adds up to a heap of opportunity once that bell goes.