Widely considered one of the greatest Lithuanian players of the 2000s, he won numerous individual awards, as well as club and national team titles.

After starting his professional career with Neptūnas, he later played for some top EuroLeague teams, such as Tau Ceramica and Olympiacos.

He announced his retirement from playing professional basketball in 2010, two years after his last club, Olympiacos, had released him following a prolonged judicial litigation.

He spent three seasons with Neptūnas, and averaged 12.7 points per game, on 53 percent field goal shooting, in the Lithuanian League.

On 17 December 2003 he scored a career-high 40 points, in a EuroLeague 2003–04 season game against the French League club ASVEL Lyon.

With Tau Ceramica, he also reached the EuroLeague's Final in 2005, where his team lost to the Israeli Super League club Maccabi Tel Aviv; which was also led by a Lithuanian player, and EuroLeague Final Four MVP, Šarūnas Jasikevičius.

However, he suffered a devastating Achilles' tendon injury in September 2006, and he only played in two games during the EuroLeague 2006–07 season.

Later that year, Olympiacos sued Macijauskas for violating his contract terms (he injured his ankle during a holiday).

Macijauskas led the senior Lithuania national team in scoring, at the EuroBasket 2003, with an average of 15.8 points per game.

[9] Macijauskas also played at the 2006 World Championship, where the Lithuanian team finished in seventh place.

He was a candidate for the Lithuanian team for EuroBasket 2009 in Poland, but at the last minute, he declared that he would not participate in the tournament.