LONDON (Reuters) – The Tennis Integrity Unit (TIU) have confirmed they are looking into a match between Alexandr Dolgopolov and Thiago Monteiro after concerns were raised over suspicious betting patterns surrounding the contest on Sunday.

A spokesman for the TIU, the anti-corruption body that covers all professional tennis around the world, told Reuters on Monday that they were making an assessment of the match while also insisting that no formal investigation had been launched.

Brazil’s Monteiro beat Ukrainian Dolgopolov 6-3 6-3 at the Winston-Salem Open, an ATP 250 event in the U.S., in Sunday’s first round match.

Monteiro, ranked 114 in the world, took just 55 minutes to beat Dolgopolov, who was ranked 51 places higher at 63, in a match which saw the Ukrainian fail to earn even one break point.

Dolgopolov had been the pre-match favorite but in the hours leading up to the match, so much money was placed on Monteiro that he started the match as an odds-on chance. It prompted several leading bookmakers to stop taking bets.

The TIU statement on Monday said it had been “made aware of concerns over betting patterns during the match.

“As with all match alerts, the TIU will assess, make a judgment and take appropriate action on the information received through its co-operative agreements with betting operators.”