- Bats Right, Throws Left
- Height 6' 0", Weight 176 lb.
- High School Rock Creek High School
Duffek went 3-0 for Krc Altron in 2007 at age 17. He played for the Czech team in the 2007 European Junior Championship, beating France but losing to future Minnesota Twins farmhand Andrey Lobanov of Russia in the semifinals; he had a 1-1, 5.40 record overall and led the Czechs with 9 strikeouts in 10 innings. At the plate, he went 2 for 11. He was at a US high school in 2006-2007 as a foreign exchange student, hoping to get a scholarship to a US college, going 16-2 with 150 strikeouts, but his eligibility for 2007-2008 was questioned even though he returned to the same school.
He went 1-1 with a 5.19 ERA for the 2009 Eagles Praha. In 2010, the southpaw was 1-3 with a 4.45 ERA for the Eagles. He starred for the Czech team that won the 2010 European Under-21 Championship, beating another Twins minor leaguer named Lobanov, Nick Lobanov, and Russia, in the Gold Medal game. He then joined the Czech senior national team for the 2010 Intercontinental Cup. He saw limited action, pitching to two batters in a loss to Cuba and four in another loss to South Korea. He gave up hits to three of the six but was charged with no runs for the event.
He did not pitch in the Extraliga in 2011-2012. Returning in 2013, he had a 6-5, 3.97 record for the Eagles. He tied Petr Minařík for 6th in the league in wins, was third in IP (95 1/3, behind Americans Trevor Caughey and Bradley Merritt) and 6th with 77 strikeouts (between Jason Daniels and Martin Drong). In the 2013 European Cup, he starred in an upset win over the host Regensburg Legionäre, allowing 3 runs (1 earned) in 7 2/3 IP (7 H, 3 BB, 5 K) before turning the ball over to Merritt. He also allowed one run in one inning after relieving Merritt against T&A San Marino.
In 2014, Duffek was 7-4 with a 3.75 ERA. He tied Boris Bokaj and T.J. Macy for third in the Extraliga in wins, was 4th in IP (between Trevor Holder and Steven Chambers) and was 8th in strikeouts (56). He was 0-1 with a 7.71 ERA in the playoffs, though. In the 2014 European Championship, he made two relief appearances for the Czechs, allowing one run in 1 2/3 IP in relief of Marek Minařík in a Czech loss to the Dutch national team and one run in two innings in closing out Bokaj's win over the French national team.
Tomáš had a 9-4, 3.73 season for the 2015 Eagles. He was 7th in the league in ERA (between John Hussey and Michal Sobotka), second in IP, 6th in whiffs (61, between Ryo Ose and Petr Minařík) and tied Petr Minařík for second in wins (one behind Jan Tomek). He fell to 1-1, 12.46 in the postseason. He was on the Czech team for the 2017 World Baseball Classic Qualifiers in March 2016 but was not used in a game.
- CEB website
- Czech Baseball Federation
- 2010 Intercontinental Cup Final Report
- 2008 article on Duffek's US high school eligibility