Rooney beat Roger Black's UK record at the Commonwealths

The UK Junior record-holder led into the final bend but Trinidadian Renny Quow eclipsed him in the final 15m and ran a lifetime best to win in 45.74.

"I lost it with my first three strides, I had a terrible start," said Rooney, whose 45.87 was not enough for second, as American Justin Oliver took silver.

Alex Nelson could give Britain a second gold in Beijing in the 200m on Friday.

Rooney's third place matched Mark Richardson's finish 16 years earlier as the best placing by a Briton in the event.

He lamented his start in the final and added: "It meant I had to start working much earlier than I should have had to make up ground.

"Coming into the home stretch I felt I could hold it, but everything went wrong and they kicked past."

Meanwhile, Harry Aikines-Aryeetey, who captured the 100m title for Britain on Wednesday, believes Nelson is capable of emulating him and said: "He's a great athlete and championship runner who can win."

Kenya's Caroline Chepkurui sped away from her two remaining rivals with 200m to go to win the women's 3,000m steeplechase in a championship record of 9 minutes 40.95 seconds, the second fastest junior time ever.

China's Huang Haiqiang pulled off a last-gasp leap at 2.32m to win the men's high jump and delight the home crowd.

His leap was the world's best this year by a teenager and just 1cm off the Asian junior record held by China's former senior world record holder Zhu Jianhua since 1982.

Estonia's Kaire Leibak won the women's triple jump with a massive final effort of 14.43m.

Croatia's Danijela Grgic timed her run to perfection to win the women's 400m to win in 50.78 seconds.

Jamaican Kaliese Spencer also ran the fastest time by a junior in the world this year to win the women's 400m hurdles in 55.11 seconds.

Russian Arkadiy Vasilyev's winning decathlon tally of 8,059 points was a championship record.

Trinidad's Renny Quow took the men's 400m in 45.74 seconds, and Kenyan Remmy Limo won the men's 1500m in 3.40.44.