An all-time Trail Blazers great has been forced to hang it up. 

Brooklyn Nets big man LaMarcus Aldridge announced on Thursday that he is retiring from the NBA after 15 seasons due to the recent discovery of an irregular heartbeat.

Aldridge, the second overall pick of the 2006 NBA draft, played the first nine years of his career in Portland. A four-time All-Star during his tenure in Rip City, Aldridge ranks high among the Blazers' all-time leaders in several statistical categories: first in rebounds (5,434), third in points (12,562), fourth in minutes (22,972) and fifth in games played (648).

Aldridge led Portland to five playoff appearances, sustained team success that no doubt contributed to the adverse reaction of many fans when he signed with the San Antonio Spurs as a free agent in the summer of 2015. 

That tension thawed over time, however, as Rip City was fully prepared to welcome Aldridge back with open arms when he parted ways with the Spurs earlier this season. Though there was reported mutual interest between he and the Blazers, Aldridge ultimately signed with the Nets, playing only five games before noticing his arrhythmia. 

The entire basketball world was shocked by the abrupt nature of Aldridge's retirement, including Blazers past and present.

Damian Lillard, who played three seasons with Aldridge, celebrated his former teammate on Instagram, posting a series of photos along with the hashtag #WhatCouldHaveBeen. Both players spoke in recent years about the unfortunate dissolution of their partnership, and how they hoped to eventually play together again.

C.J. McCollum wasn't an integral cog for Portland during his two seasons as Aldridge's teammate, not emerging as a starter until Aldridge left for San Antonio. McCollum paid his respects to the seven-time All-Star on Twitter.

Robin Lopez played two seasons with Aldridge, including 2014-15, when the Blazers got off to a 41-19 start before Wes Matthews tore his Achilles. He recalled some specific memories at a local car dealership while feting Aldridge.

Jamal Crawford enjoyed just one season in Portland, 2011-12. Still, Aldridge clearly left quite an impression on the Pacific Northwest icon during their brief time as teammates.

Next up for Aldridge? Rest, relaxation and some well-deserved time with family – and eventually, a ceremony in Portland that raises his No. 12 to the Moda Center rafters.

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