Gay beats Powell in Gateshead 100m
American Tyson Gay recovered from a poor start to beat rival Asafa Powell over 100m in 9.93 seconds at the British Grand Prix in Gateshead.
Jamaican Powell started well but Gay fought back into a slight headwind to win the Diamond League event.
It was Olympic and world silver medallist Gay's seasonal debut over 100m following a hamstring problem.
Britons Lisa Dobriskey and Phillips Idowu both won but Jessica Ennis had a mixed day on her return from illness.
Powell, returning to the track where he equalled his former world-record time of 9.77 seconds in 2006, had promised a fast time but failed to deliver in the final.
Gay had won the opening heat in an impressive 9.96 seconds and managed to go even faster to seal his victory.
"I feel good. He's one of my favourite competitors and I managed to get him today," said the American.
"I really had to stretch to the finish line and he didn't see me coming so I got the victory.
"The hamstring is still tight and that is something I am going to have to work on."
Powell said: "I got out very well but then I started to ease up a bit too much. Then I saw Tyson coming and I could not pick it up.
"But we are in good shape and this is how it's going to be all season, he'll win some and I'll win some."
Powell will take on compatriot Usain Bolt in Paris next Friday, with the Olympic champion the favourite after running 9.82 in Lausanne on Thursday on his return from injury.
World heptathlon champion Ennis was left deflated after a disappointing return to the track.
Dobriskey shows class to win 1500m
The 24-year-old has just recovered from a virus and ear infection and could only manage last place in the 200m.
"I'm a little bit disappointed if I'm honest," she said. "I would have liked to have run quicker. I'm not sure what the wind was but it felt quite breezy."
But there was better news for Ennis in the javelin as she threw a season's best of 46.15m in the second round, just 0.32m below her personal best.
World champion Idowu won the triple jump with a best of 17.38m, but world bronze medallist Jenny Meadows could only finish eighth in the 800m as her comeback from injury continues.
Dobriskey put in another impressive performance to win the 1500m in style.
The Commonwealth champion confirmed her return to form following injury with a time of 4:03.69, ahead of American Morgan Urceny and fellow Briton Hannah England.
England won the European trials with Dobriskey back in third, but world silver medallist Dobriskey ran a quick time in Lausanne on Thursday evening to move top of the British rankings.
"I was really pleased with my performance in Lausanne, it was a lot more than I expected, and today was fantastic," she said.
"There are a couple of areas I still need to work on but I have the time to do it."
Mo Farah missed out on breaking the British record for 5000m but did set a new personal best of 13:05.66, although that was only good enough for seventh place in a race won by Kenya's Vincent Chepkok in a meeting record of 13:00.20.
Britain's Martyn Rooney warmed up for the European Championships in Barcelona later this month with an below-par display in the 400m.
Rooney, who has twice dipped under 45 seconds in the 400m this year, gave himself far too much to do in the final straight and finished third in 45.44.
Jamaica's Ricardo Chambers won the race in a season's best 44.98 with Britain's Michael Bingham second in 45.08 - also a season's best.
"It was a very sluggish performance. I didn't do anything down the back straight and if you don't do that you're not going to execute the race properly," said Rooney.
"It's just a bad performance and something I will have to get out of the system before the Euros in the next couple of races."
Andy Baddeley had more reason to be cheerful, however, after getting close to a personal best time in the 1500m.
Baddeley clocked an impressive 3:34.50 but still could only manage fifth place, with in-form Kenyan Asbel Kiprop easing to victory in 3:33.34.
Andy Turner finished second in the 110m hurdles in a time of 13.41, with Jamaican Dwight Thomas winning in 13.38.
Former world silver medallist Nicola Sanders could only manage seventh in the 400m.
The Gateshead event is the first of two Diamond League meetings to be staged in Britain this summer.
The second is a two-day competition at Crystal Palace on 13-14 August which comes two weeks before the European Championships.