2008 Summer Olympics

Titenis guaranteed his spot on the Lithuanian team for the 2008 Summer Olympics in Beijing, by obtaining an A-standard entry time of 1:00.92 (100 m breaststroke) from the 2007 FINA World Championships in Melbourne, Australia.^[5] On the first night of the Games, Titenis challenged seven other swimmers in a top seeded heat, including former Olympic medalists Roman Sludnov of Russia (2000), and Brendan Hansen of the United States (2004). He picked up a second spot by nearly half a second (0.50) behind France's Hugues Duboscq, lowering his time to 1:00.11.^[6] At the end of the evening preliminaries, Titenis recorded a sixth fastest time to advance further into the semifinals.^[7] The following morning, Titenis fell short in his bid for the final, as he placed twelfth in the semifinal run by five hundredths of a second (0.05) behind Bulgaria's Mihail Alexandrov, with a fourth slowest time of 1:00.66.^[8]

2009 season

2011 season

At the 2011 FINA World Championships in Shanghai, Titenis competed for the second time in all breaststroke events. For his first event, 100 m breaststroke, Titenis finished in a sixth-place tie with Hungary's Dániel Gyurta, with a time of 1:00.25.^[19] The following morning, Titenis failed to improve both his performance and a national record of 27.57 seconds in the preliminary heats of the 50 m breaststroke, with a time of 28.14. For his third and final individual event, 200 m breaststroke, Titenis recorded a fastest time of 2:10.33 in the preliminary heats, but managed to finish only in sixth place on the final round by four tenths of a second (0.40) behind Great Britain's Michael Jamieson, clocking at 2:11.07.^[20][21]

Few weeks after the World Championships, Titenis rebounded from his loss by winning two gold medals in the same stroke at the 2011 Summer Universiade in Shenzhen, China. He tied with New Zealand's Glenn Snyders for the 200 m breaststroke title at 2:10.85, but edged him out of the gold medal in the 100 m by thirty-two hundredths of a second (0.32), posting his time of 1:00.39.^[22][23][24]

2012 Summer Olympics

Four years after competing in his first Olympics, Titenis qualified for his second Lithuanian team, as a 23-year-old, at the 2012 Summer Olympics in London, by clearing two FINA A-standard entry times of 1:00.25 (100 m breaststroke) and 2:10.33 (200 m breaststroke), both from the 2011 FINA World Championships in Shanghai, China.^[25][26]

On the first day of the Olympics, Titenis recorded the third fastest qualifying time of 59.68 in the preliminary heats of the 100 m breaststroke by six hundredths of a second (0.06) behind Australia's Christian Sprenger.^[27] He lowered his time to 59.66 in the semifinals, but was unable to break a minute barrier, when he finished eighth in the final by nearly a second behind Italy's Fabio Scozzoli at 1:00.84.^[28][29][30] Achieving his best finish, Titenis became the second Lithuanian swimmer in history to reach an Olympic final since Vytautas Janušaitis did so in 2004, until his teammate Rūta Meilutytė surprisingly won the gold medal in the same stroke by the following evening.

Three days later, Titenis challenged seven other swimmers on the fifth heat of the 200 m breaststroke, including two-time Olympic champion Kosuke Kitajima of Japan. He edged out Germany's Marco Koch to snare a third spot in his heat by a quarter of a second (0.25) in 2:10.36. Titenis recorded an eighth fastest time in the preliminary heats to secure his spot for the semifinals.^[31] On the evening session, Titenis failed to qualify for the final as he finished his semifinal run in eleventh place, dipping under a 2:10 barrier and lowering his qualified entry time to 2:09.95.^[32]

2016 Summer Olympics

Swimming two individual races and a relay in his third Olympics, Titenis failed to reach any finals, being at most a semifinalist in the 100 m breaststroke with 59.80.^[33]