Flora Duffy will begin the defence of her ITU World Triathlon Series title when she competes in Yokohama, Japan, this weekend.

Duffy missed the opening two races of the series in Abu Dhabi in March and the Gold Coast, Australia, last month because of an injury which prevented her from running.

The 29-year-old will be eager to make up ground on rivals such as Andrea Hewitt, of New Zealand, who has made a flying start after winning the first two events. Hewitt, 35, is likely to be Duffy’s biggest threat this season and has been unstoppable so far, proving that she is the top competitor in both a sprint and standard-distance setting.

With the field in Yokohama including Britain’s Jessica Learmonth and Lucy Hall, Duffy may look to “team up” with the pair of swim-bike specialists as she did when she won in Stockholm and most significantly the Grand Final Cozumel in Mexico last season.

It is possible that Duffy’s competitors may look to counter her “race from the front” tactics that brought her so much success during what was an outstanding campaign, which also saw her retain both her Xterra and ITU Cross Triathlon World Championships.

Duffy has developed her run to compete off the bike, even without a lead, although with limited training during the past few months because of her injury, it is difficult to foresee how she will fare this weekend.

After Yokohama there are still five races remaining in the series and with the Grand Final in Rotterdam in September serving up double points, there is still time for Duffy to retain her title.

However, she will need to get off to a solid performance this weekend in a competitive women’s field, including Hewitt who will be vying for a third successive victory and Australian Charlotte McShane, last year’s bronze medal-winner in the Grand Final. Ai Ueda and Uri Ide, both of Japan, have also made encouraging starts to the series.

n Tyler Butterfield will return to action on Sunday when he competes at the Monterrey Ironman 70.3 in Mexico.

Butterfield had an excellent third-place finish at the Ironman North American Championships in Texas last month and will start as one of the favourites.

Brent McMahon, of Canada, will likely be another main contender if he competes.

McMahon finished sixth at the Ironman 70.3 Utah last weekend and may opt not to race on successive weekends.