Ciara Mageean's Dream Mile at the Diamond League meeting in Oslo proved anything but, with the Portaferry athlete trailing home in a disappointing 11th place in four minutes 22.03 seconds as Birke Haylom of Ethiopia set an Under-20 world record and broke Sonia O'Sullivan’s meeting record.Mageean became outpaced on the penultimate lap but stayed on in the closing stages to finish ahead of three of her rivals.The 31-year-old came into the race in a rich vein of form having set a new Irish 800m record at the British Milers Club event in Manchester at the end of May, as well as clocking 4:00.95 when fourth in the 1500m at the Florence Diamond League meeting earlier this month.Seventeen-year-old Haylom delivered a confident display of front running in the rarely-raced women’s mile as she broke clear halfway through the third lap and held on to win in 4:17.13.Elsewhere at Bislett Stadium, Karsten Warholm and Jakob Ingebrigtsen delivered stunning performances in front of their adoring fans, winning the 400m hurdles and 1500m in spectacular times.Warholm, who set the world record of 45.94 seconds at the Tokyo Olympics, was running his first race of the season but destroyed the field and, even with a slight stutter off the final barrier, came home in 46.52, the fourth fastest time in history."When you're on the track, you're in the bubble but I really felt the crowd lift me in the home straight - the adrenaline was really pumping in the last 100m," Warholm said."It was a race I will always remember - I felt really good today and knew something special was coming."Today shows in the right circumstances, I can really attack the world record, maybe even this year.