- Bats Right, Throws Left
- Height 6' 0", Weight 160 lb.
Martin Gieci has pitched for the Slovakian national team.
Gieci allowed one run in one inning for Apollo Bratislava in the 2019 European Interleague, at age 16.  The league was canceled in 2020 due to the COVID-19 pandemic. He debuted for Slovakia's national team in the 2021 European Championship Qualifier, allowing three hits, three walks and three runs in two innings in a start against Ireland; Daniel Just relieved and Slovakia rallied to win the game and would win the tournament to make their first European Championship.  In the 2021 European Championship, he got the start against the Czech national team. Facing a team with three former minor leaguers and several others with US college experience, he held a 3-2 lead over Radim Chroust entering the 5th before allowing two runs that inning. Jaroslav Kasna took over and Gieci took the loss in a big mismatch, having held his own for most of the game. The teenager played a critical role in the 15th/16th place game versus France. Relieving Michal Puškár with one out in the second, a 2-1 lead and two on, he gave up a run-scoring force to Martin Vissac. Slovakia scored in the bottom of the second, then France scored in the third. Gieci then blanked France for four straight innings (France's team included two former minor leaguers and a former indy leaguer) and Slovakia took a 4-3 lead into the 8th. France tied it in the 8th then Marek Bošanský came in, but Gieci had kept Slovakia in the game well. His 4.09 ERA for the Euros beat the team mark of 7.28 handily and his 11 innings led the squad, two more than their one player with US pro experience, Jakub Ižold. He tied Enorbel Márquez, Andrei Lobanov and Dimitri Kourtis for 10th in the event in innings pitched.