Achievements Grigoriu has a career high Association of Tennis Professionals singles ranking of 1496 achieved on 15 August 2011. He also has a career high Association of Tennis Professionals doubles ranking of 282 achieved on 17 November 2014. Grigoriu won his first Association of Tennis Professionals Challenger Tour doubles title at the 2014 Internazionali di Tennis Castel del Monte, partnering Costin Pavăl, defeating Roman Jebavý and Andreas Siljeström in the final, 7–6(7–4), 6–7(4–7).