[2] On the first day of the Games, Matsa teamed up with Nery Mantey Niangkouara, Eleni Kosti, and Zoi Dimoschaki in the 4 × 100 m freestyle relay.

Swimming in heat seven, she edged out Trinidad and Tobago's Sharntelle McLean to pick up a seventh spot by four-tenths of a second (0.40) in 26.46.

[7] She challenged seven other swimmers in heat nine, including Slovakia's top favorite and five-time Olympian Martina Moravcová.

She raced again to seventh place in 25.68, just a slimmest margin off her entry time, and 0.03 of a second behind Ukraine's Oksana Serikova.

[8] Matsa was also selected as a reserve for the Greek squad at the 2012 Summer Olympics in London, but did not compete in the 4 × 100 m freestyle relay.