He began his stage career in 1998 as an understudy for the roles of Dennis Ziegler and Warren Straub in the Off-Broadway production of the critically acclaimed play, ‘This is Our Youth,’ of American dramatist and screenwriter Kenneth Lonergan at the Second Stage Theatre.
A 1999 off-Broadway Second Stage Theatre revival of the play, ‘Gemini,’ that closed after fourteen performances featured him in the role of Randy Hastings. Moving on, he was associated with several other stage productions, including the plays ‘The Hot l Baltimore’ (2000), ‘The Skin of Our Teeth’ (2000), and ‘Street Scene’ (2001), staged at the Williamstown Theatre Festival, Williamstown, MA.
Meanwhile, he made his big-screen debut with the 2000 teen romantic comedy film, ‘Loser,’ by Amy Heckerling.
He made his Broadway debut in 2004 with the play ‘Reckless,’ which was staged at the Biltmore Theatre, New York, NY.
His stage career was bolstered by several other productions before he got one of the most notable stage portrayals of his life, when he appeared as Greg in Neil LaBute's play, ‘Reasons to be Pretty.’ Directed by Terry Kinney and produced by MCC Theater, the play premiered on June 2, 2008 at the Off-Broadway Lucille Lortel Theater where it had a sold-out run till July 5.
The previews of Broadway production of ‘Reasons to be Pretty’ began on March 13, 2009, at the Lyceum Theatre while it opened on April 2 that year and ran for 85 performances till June 14, 2009. Sadoski’s brilliant performance in the critically acclaimed play earned him several award nominations, including a Tony Award nomination for ‘Best Performance by a Leading Actor in a Play,’ and a ‘Drama Desk Award’ nomination for ‘Outstanding Actor in a Play,’ in 2009.
He is the narrator of the audiobook recording of Stephen King's novella, ‘Mile 81,’ that released in January 2011. Other voice over works of Sadoski includes a radio play, ‘reasons to be pretty,’ (2013) and an audiobook, ‘Zero K,’ (2016) by ‘Don DeLillo’.
He appeared as Trip Wyeth in Jon Robin Baitz’s play, ‘Other Desert Cities,’ in Off-Broadway production on January 13, 2011. It was named by the ‘Outer Critics Circle’ as ‘Outstanding New Off-Broadway Play.’
‘Other Desert Cities’ was transferred to Broadway on November 3, 2011, at the Booth Theatre. The play emerged among the finalists of the ‘Pulitzer Prize for Drama,’ in 2012. Earlier in 2011, it fetched Sadoski an ‘Obie Award’ for ‘Distinguished Performance by an Actor’ and a ‘Lucille Lortel Award’ in the category of ‘Outstanding Featured Actor in a Play.’
In 2011, he appeared as Don Keefer in the political drama series, ‘The Newsroom.’ It is considered among his most notable portrayals. The series premiered on HBO on June 24, 2012, and ran for 3 seasons encompassing 25 episodes till December 14, 2014.
He played the starring role of Paul in the Jean-Marc Vallée directed biographical adventure drama film, ‘Wild,’ that premiered at the Telluride Film Festival on August 29, 2014, and was screened at the ‘Toronto International Film Festival’ and ‘San Diego Film Festival’ on September 8 and September 24 respectively before releasing in North America on December 3.
He starred as Donny in the Adam Salky directed drama film, ‘I Smile Back,’ which had its world premiere on January 25, 2015, at the Sundance Film Festival. It was also selected for screening at different film festivals, including the ‘Toronto International Film Festival’ on September 16, 2015, before having a limited release on October 23. Some other notable big-screen flicks featuring Sadoski are ‘John Wick’ (2014) and ‘John Wick: Chapter Two’ (2017).
Television miniseries, ‘The Slap,’ which was aired for a season consisting of 8 episodes on NBC from February 12, 2015 to April 2, 2015, featured him in the role of Gary.
Sadoski appears in the starring role of Matthew "Matt" Short in the CBS aired American sitcom television series ‘Life in Pieces’ since September 21, 2015. The series has already completed three seasons and has been renewed for a fourth season by CBS on May 12, 2018.