|Date of birth||29 July 1984|
|Place of birth||Drăsliceni, Moldavian SSR|
|Height||1.77 m (5 ft 10 in)|
|Playing position||Defensive Midfielder|
|2006||FC KAMAZ Naberezhnye Chelny||3||(0)|
|2011–2012||→ Dacia Chişinău (loan)||16||(2)|
* Senior club appearances and goals counted for the domestic league only and correct as of 22:57, 6 June 2019 (UTC)|
‡ National team caps and goals correct as of 8 February 2014
Onica began playing football with local side Izvorash Draslicheny at age 12. He joined FC Unisport-Auto Chişinău next before a move to Russia where he played for FC Spartak Chelyabinsk and FC KAMAZ Naberezhnye Chelny. Upon returning from Russia, he joined FC Dacia Chişinău where he would be named the top central midfielder in the 2009 Moldovan National Division by the FMF.
Onica joined Vorskla Poltava on a free transfer in December 2009, signing a three-year contract with the club.
In July 2013 he signed a contract with Lokomotiv Tashkent. On 31 July 2013 he made his debut for Lokomotv in the Uzbek Cup semifinal match against Bunyodkor. In January, he signed for another Uzbekistan club Neftchi Farg'ona FK. Alexandru scored his first goal in Uzbekistan higher division on 22 June against FK Andijan.
Onica has made eight appearances for the Moldova national football team. He played for the under-21 national team before making his senior debut in a friendly against Estonia on 18 November 2008.
- Kharchenko, Boris (16 December 2008). Газета "Время" вручила молдавскому футболисту специальный приз – "Дебют в сборной" (in Russian). Gazeta Vremya.
- Александр Оникэ подписал контракт с "Ворсклой" (in Russian). Sports.md. 23 December 2009.
- "Bunyodkor-Lokomotiv, 2013 Uzbekistan Cup" (in Russian). soccerway.com. 31 July 2013.
- Mamrud, Roberto (29 October 2009). "Moldova – Record International Players". RSSSF.
- Оникэ забил гол "Тилигулу" и отправился на собственную свадьбу (in Russian). Moldfootball.com. 23 November 2008.