He had a promising career in baseball as a pitcher until he suffered a rotator cuff injury that hindered his chances to pitch at the professional level.

Tonelli attended several small colleges in California in hopes of rehabilitating his shoulder and professional baseball pitching career.

After leaving baseball in 1997, he fell into the fashion industry by chance and traveled throughout Southeast Asia as a print and runway model, working for companies such as Donna Karan, Versace, Levi's, and Louis Vuitton.

In 2007, Tonelli returned to Singapore where he was seen in the MediaCorp English programme Life Story featured as the American coach of Ang Peng Siong.

He continued working for Channel 8, appearing in the Mandarin drama series Double Bonus,[6] playing the part of Michael, the ex-boyfriend of Peiling, played by actress Tracy Lee, and then followed by co-starring in the 30th anniversary blockbuster drama series Joys of Life acting opposite Rui En.

In 2017, Tonelli can be seen as the co-host of Channel 5 Steady lah!, Celebrity Car Wars season 2 and appeared in a deleted scene of Crazy Rich Asians.

[14] In early 2015, after four years on radio, Tonelli left to focus on personal business ventures, acting in television and film, and emcee work.

[15] The host of Celebrity Car Wars, an hour-long action reality series, consisting of 8 week road of automotive discovery.