USA’s track athletes were left with bloody noses at the World Relays on Sunday but ultimately emerged victorious after a bruising two days of competition here.American joy at finishing on top of the medals table with five golds will be tempered by the disappointment of losing its proud unbeaten record in the 4x400m after electrifying performances from Poland and Trinidad and Tobago.USA had dominated the event at the three previous editions but was stunned by the Polish women as Justyna Swiety-Ersetic anchored the European champion to an upset win in three minutes, 27.49 seconds.The Americans came up just short, the hot favourite settling for silver in 3:27.65 with Italy taking the bronze.“We can’t believe it,” said Patrycja Wyciszkiewicz. “It was such an amazing feeling to actually hit the line first.”Astonishing run Lightning struck again in the men’s 4x400m final when Machel Cedenio produced an astonishing last 100m to give world champion Trinidad and Tobago gold in a photo finish with Paul Dedewo.Cedenio ran a 44.41 split to give his team victory in a world-leading 3:00.81 — three hundredths ahead of the Americans, who were later disqualified, bumping Jamaica up to the silver and Belgium to third.USA hit back in the…