Star Philadelphia point guard Simmons was thought a chance to be called up after Washington's Wall was sidelined from the February 18 showpiece game with a knee injury. Brown is probably fourth in the Celtics' pecking order, an impressive feat to obtain on the Eastern Conference's top-seeded team, but not exactly All-Star worthy.
Among the Heat's All-Star possibilities are guard Goran Dragic and center Hassan Whiteside.
The league announced today that commissioner Adam Silver has selected Drummond as the replacement.
Another star chosen to be in the 2018 NBA All-Star Game had to unfortunately be replaced, and - of course - not all players were happy about the replacement choice.
Drummond will take his place on LeBron James' team for the match at the Staples Centre in Los Angeles.
Following the news, a couple of National Basketball Association players took to Twitter to react to Drummond being named an All-Star. After Drummond was given the All-Star game berth, Brown took to Twitter to show his confusion at the perceived snub. Sixers center Joel Embiid was voted in as a starter.
Because Wall was representing the Eastern Conference, his replacement must be from that side also, hence why Lou Williams wasn't upset this time around.
Brown now is Boston's second-leading scorer behind Kyrie Irving at 14.1 points per game - ahead of Rookie of the Year candidate Jayson Tatum and All-Star Al Horford - so the Pistons big man might be a little off base there.
The Heat's only All-Star selections over the franchise's 30 seasons remain Mourning (five selections with the Heat), Tim Hardaway (two), Anthony Mason (one), Shaquille O'Neal (three), James (four), Bosh (six) and Wade (12).