The organisation tackling the threat of match-fixing in tennis has received 48 alerts this year, mostly from the lower tiers of the professional ranks. A briefing note from the Tennis Integrity Unit (TIU) said 24 men’s matches on the Futures Tour and 10 women’s matches from the entry-level ITF circuit had aroused suspicion.

One grand slam match triggered an alert and one from the WTA Tour but there were none from the men’s ATP Tour. The men’s Challenger circuit, one rung below the main Tour, had seen 12.

Alerts are forwarded to the TIU from the betting industry when there is “unusual or suspicious activity” around a match.

A full investigation can follow should the TIU believe corrupt activity was likely, although it said alerts were not necessarily indications of wrongdoing.

“Every alert received by the Tennis Integrity Unit is assessed and followed up as an indicator that something inappropriate may have happened,” the TIU said in a statement.

“It is important to appreciate that an alert on its own is not evidence of match-fixing. There are many reasons other than corrupt activity that can explain unusual patterns.”

The reasons, it states, can be incorrect odds setting, player fatigue or injury and playing conditions. There have been 24,110 professional matches played this year.