A Blues rugby star tipped to be a future All Black has dodged a conviction for drink driving.

The New Zealand under-20 and Blues wing Tevita Li has been discharged without conviction and ordered to just pay the costs of taking and testing his blood alcohol levels.

NZME reports the 19-year-old pleaded guilty to driving with a blood-alcohol reading of 45mg [ milligrams] at the Manukau District Court back in July.

The legal limit for under 20s is zero.
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In delivering his decision the judge said a conviction would provide a real impediment to what so far has been a stellar career.

Mr Li's clean record will also keep the door open for a career in the police once he's finished playing.