Borzakovskiy's greatest achievement was his victory in the 800 m race at the Athens Olympics in 2004. By this point, he was well known for sitting back until about the last 200 metres and then using a great kick to catch up and win, reminiscent of the tactics of U.S.A's Dave Wottle. At the Olympics he employed the same strategy, using this 'late charge' to come from behind in the last 150 meters to pass Wilson Kipketer, who was leading with only 20 metres to go, and take the victory.
In 2008 he made an impressive comeback by posting a time of 1:42.79 minutes, his first time under 1:43 since 2001. He made the Olympic team at the Beijing Olympics but unexpectedly failed to qualify for the 800 m final, finishing only third in his semifinal heat.
In 2011, he achieved yet another podium finish with a bronze medal in the 800 meters at the 2011 IAAF World Outdoor Championships. In this race, Borzakovskiy ran most of the last lap in second place and was himself overtaken just before the finish line.
In 2012, he won the European Championship 800 metre gold medal, in Helsinki. At the 2012 London Olympics, he failed to make the finals as he was eliminated in the semi-final round.