Nick Willis ran the seventh 5000m race of his illustrious career tonight but those numbers might stack up more quickly if he enjoys continued success in the event. The Olympic 1500m silver medallist is considering doubling up and racing both the 1500m and 5000m at London. He won\'t, however, do it if even the smallest injury flares in training but things are going so well he\'s bullish about his prospects. Tonight he defended his 5000m title at the New Zealand track and field championships in Waitakere, dominating a field that also contained his American training partner and Olympic hopeful Will Leer. The pair were joined by two other runners in a breakaway as early as 200m into the race but cleared out with six laps to go. Willis then scooted ahead with three laps remaining and won in a time of 13 minutes, 54.29 seconds, with Leer 11 seconds behind in second. He would need to carve more than 30 seconds off that time to qualify for London but, given he is in a high training block and had already run 150km this week and went for 25km runs on both Tuesday and Wednesday, doesn\'t think it would be a problem. \"I think [I have run] only five or six [5000m events] in my life but only really one at a full crack at it back in 2005 at the university champs in the States when I finished third in 13:27. If I could run 13:27 sevens years ago, and that was on a hot day without pacemakers, it shouldn\'t be a problem [to qualify] but we will have to wait and see. \"I know I should be able to run under 13:10 for the 5k given good healthy training. It\'s just a matter of being able to do that. It\'s much easier said than done.\" It\'s why he won\'t take any risks. The 1500m remains the priority but he\'s he\'s keen to expand his programme and believes racing the 5000m at London would give him options as well as be good experience with Rio de Janeiro 2016 in mind. Willis was the headline act on the first day of the national championships that also features a number of other Olympic hopefuls. Monique Williams took her first tentative step back in competition after a troubling plantar fascia injury in winning the 100m. She did it by the narrowest of margins, clocking the same time of 11.95 seconds as Auckland\'s Rochelle Coster, but it was a good result considering she returned to training only last week. She is targeting the 200m in London, and would need to run quicker than 23 seconds to do that, but believes the layoff might work in her favour. \"I could time it perfectly by getting the qualifying time in late June and then go into the Olympics in form,\" she said. \"In a way, if it works out, it could be really good.\" It didn\'t end as well for three-time defending champion Carl Van Der Speck in the men\'s 100m as he had to settle for third behind Joseph Millar (10.36s) and Isaac Tatoa. Heptathlete Sarah Cowley won the women\'s long jump with a distance of 5.74m and will also compete in the shot put and javelin as well as 4x100m and 4x400m women\'s relays. She needs to add another 92 points to her personal best in the heptathlon to qualify for London and will attempt to do that at events in Austria in May and Germany in June. Most attention tomorrow will focus on Nikki Hamblin, who has already qualified for London in the 1500m but needs to convince selectors she is over her Achilles injuries. Jacko Gill will compete in the under-20 shot put and Liz Lamb will contest the high jump.