Žilina When playing for MSK Žilina from 2004 to 2007, the team became Slovak champion in
2007.
Erzgebirge Aue In August 2007, he signed a loan deal with the
2. Bundesliga side
Erzgebirge Aue where he scored ten goals and provided seven assists in 29 games.
Genk On 11 June 2008, Nemec signed a four-year deal with Belgian club
KRC Genk. He remained at the club for only one season however, in which he scored four goals in 21 matches.
Kaiserslautern In July 2009, he was involved in talks over a move to
Scottish Premier League club
Heart of Midlothian which ultimately failed. On 28 July 2009, however, Nemec signed a three-year contract for
1. FC Kaiserslautern, returning to Germany's second division. Reportedly falling from a
cherry tree in his garden in June 2011, Nemec suffered injuries including broken ribs, a broken collarbone that required surgery, and a
concussion which kept him out of football for about three months. He returned to training in early September. He left the club during the mid-season break in January 2012, after having appeared in 61 league matches and scoring nine goals in his two and a half seasons.
Ingolstadt 04 On 27 January 2012, Nemec joined
FC Ingolstadt until the end of the season. He made his competitive debut for the club on 4 February 2012 in a 1–1 draw in the league with
Fortuna Düsseldorf.
Union Berlin On 24 July 2012, he signed a two-year contract with
Union Berlin in the German second division until June 2014. In December 2013, his contract was extended until 2016 including an option for another year. Only five months later though, in April 2014, the club announced it had released him, however he stayed with Union. After playing in just five games through the first half of the season, his contract was terminated in January 2015. Union manager
Norbert Düwel said: "It is a pity that cooperation has not worked as both sides had imagined. Under these circumstances, it is better to part ways."
New York City On 25 January 2015, he signed with
New York City FC ahead of their first season in
Major League Soccer. He made eight starts for the team in nine overall appearances, although he did not score a goal or record an assist during that time. On 31 August 2015, New York City FC and Nemec mutually agreed to terminate his contract. In his first season with the club, on 20 May 2017 Nemec scored two goals in the final of the
2016–17 Cupa Ligii. Dinamo defeated
ACS Poli Timișoara 2–0 and won this trophy for the first time in history. At the same time, it was the only trophy Nemec won in Romania. On 10 May 2018, Dinamo's coach
Florin Bratu confirmed, that after expiration of his contract with Dinamo, Nemec wants to leave the club. At the national team meeting, on 29 May, Nemec confirmed that his intention to depart and added, that his subsequent contract will be his last professional one, adding that he seeks a financially attractive deal or else he prefers a return home. On 29 August 2020, he returned to
Dinamo București on a one-year contract, with an option for an additional year.
Pafos On 27 August 2018, he joined
Pafos of the
Cypriot First Division on a one-year contract, with an option for an additional year. He scored 16 goals in the league, winning the
golden boot as well. ==International career==