Dan Evans says he still considers himself to be the British number three – despite being overtaken by Aljaz Bedene in the world rankings.
British number four Evans, 26, dropped to 58th in Monday’s latest standings, two places below Slovenia-born Bedene.
i don't think he really believes he's British either
Bedene, 27, moved to the UK in 2008 and switched nationality in March 2015.
“I don’t think he really believes he’s British either,” said Evans after losing in the Madrid Open first round to Robin Haase on Monday.
“It’s nothing against Aljaz. I like him, he’s not confrontational in any way – but to me it doesn’t sit well if you play for another country.
“I don’t feel bad about him, but for me it’s a bit baffling as to why.”
The BBC has contacted Bedene for his response to Evans’ comments.
It is not the first time Evans has spoken out against Bedene’s switch, with the player previously saying – before the change of allegiance was confirmed – Bedene should not be allowed to represent Britain in the Davis Cup.
International Tennis Federation rules do not allow players to represent more than one country in the Davis Cup.
Bedene, who has represented Slovenia in three ties, had an attempt to overturn his ban and play for Britain rejected by an arbitration hearing in March.
Evans went out early in Madrid after losing 7-5 6-2 against Dutchman Haase, who is ranked 13 places higher at 45th in the world.
Evans lost his serve in the opening game, breaking back for 5-5 but then failed to hold in the next game.
Haase raced into a 4-0 lead in the second set and, although Evans managed to get a couple of service games on the board, eased to victory in 80 minutes.
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Evans, who rates clay as his least favourite surface, did make his opponent work in what proved to be final game, spurning three break points before Haase, 30, took his fourth match point.
Britain’s world number one Andy Murray, who received a first-round bye, will play Romania’s Marius Copil in his opening match on Tuesday.
Meanwhile on cout…
The Scot, 29, finished runner-up in Madrid last year, losing to Novak Djokovic in the final.
Johanna Konta, Britain’s leading female player, continued her own struggles on clay with a final-set slump during her defeat by Laura Siegemund in the first round of the Madrid Open on Sunday.