He turned professional for the 2005 season in Denmark based Team CSC, where he signed a two-year contract.

For the start of the 2006 season, he once again showed himself in Tour of Qatar, finishing as the best young rider of the race for the second year in a row.

He showed his good form in March with a third-place finish in Le Samyn, being beaten only by Philippe Gilbert in the bunch sprint of the peloton, and a few days later he sprinted his way to second place at stage 2 of the Driedaagse van West-Vlaanderen where he was second only to world class sprinter Robbie McEwen.

He maintained his good form through the season and also came in 2nd in the Danish Road Racing Championship, only beaten by his teammate Nicki Sørensen.

In August he won two stages at Tour of Denmark and also led the overall classification until the final time trial securing him a total fifth place.

Only a week later Breschel rode very impressively at the world cycling championships finishing 3rd and getting a bronze medal.

[1] In his return to the former Team CSC squad, Breschel managed to pick up four stage wins at the Danmark Rundt – two each in 2013 and 2015.

Breschel did not have the best year at Astana, and his best result was 12th at Dwaars door Vlaanderen, a race he had previously won in 2010.