Question: When was it announced that Marc-Andre Fleury would the Vegas Golden Knights because of the NHL expansion draft?

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1988 NBA Expansion Draft: The 1988 NBA Expansion Draft was the eighth expansion draft of the National Basketball Association (NBA).  The draft was held on June 23, 1988, so that the newly founded Charlotte Hornets and Miami Heat could acquire players for the upcoming 1988–89 season.  Charlotte and Miami had been awarded the expansion teams on April 22, 1987.  In an NBA expansion draft, new NBA teams are allowed to acquire players from the previously established teams in the league.  Not all players on a given team are available during an expansion draft, since each team can protect a certain number of players from being selected.  In this draft, each of the twenty-three other NBA teams had protected eight players from their roster and the Hornets and the Heat selected eleven and twelve unprotected players respectively, one from each team.  Prior to the draft, the league conducted a coin flip between the Hornets and the Heat to decide their draft order in this expansion draft and in the 1988 NBA draft.  The Hornets won the coin flip and chose to have the higher pick in the 1988 Draft, thus allowing the Heat to receive the first selection and the right to select twelve players in this expansion draft.

2017–18 Pittsburgh Penguins season: The 2017–18 Pittsburgh Penguins season will be the 51st season for the National Hockey League ice hockey team that was established on June 5, 1967.  They will enter the season as two-time defending Stanley Cup champions.  It will be the first season since the 2002–03 season in which the team will play without goaltender Marc-Andre Fleury, who was drafted to the Vegas Golden Knights in the expansion draft.

1989 NBA Expansion Draft: The 1989 NBA Expansion Draft was the ninth expansion draft of the National Basketball Association (NBA).  The draft was held on June 15, 1989, so that the newly founded Minnesota Timberwolves and Orlando Magic could acquire players for the upcoming 1989–90 season.  Minnesota and Orlando had been awarded the expansion teams on April 22, 1987.  In an NBA expansion draft, new NBA teams are allowed to acquire players from the previously established teams in the league.  Not all players on a given team are available during an expansion draft, since each team can protect a certain number of players from being selected.  In this draft, each of the twenty-three other NBA teams had protected eight players from their roster and the Timberwolves and the Magic selected eleven and twelve unprotected players respectively, one from each team.  Last year's expansion teams, the Charlotte Hornets and the Miami Heat, were not involved in the expansion draft and did not lose any player.  Prior to the draft, the league conducted a coin flip between the Timberwolves and the Magic to decide their draft order in this expansion draft and in the 1989 NBA draft.  The Magic won the coin flip and chose to have the first selection and the right to select twelve players in this expansion draft, thus allowing the Timberwolves to receive the higher pick in the 1989 Draft.

2017 NHL Expansion Draft: The 2017 NHL Expansion Draft was an expansion draft conducted by the National Hockey League on June 18–20, 2017 to fill the roster of the league's expansion team for the 2017–18 season, the Vegas Golden Knights.  The team's selections were announced on June 21 during the NHL Awards ceremony at T-Mobile Arena.

Erik Brännström: Erik Brännström (born 2 September 1999) is a Swedish professional ice hockey defenseman.  He is currently playing with HV71 of the Swedish Hockey League (SHL) as a prospect to the Vegas Golden Knights of the National Hockey League (NHL).  His older brother, Isac Brännström, is also an SHL player, currently with HV71.  He was selected 15th overall by the Golden Knights in the 2017 NHL Entry Draft, Vegas' third pick of the first round.

List of Vegas Golden Knights head coaches: The Vegas Golden Knights are an American professional ice hockey team based in the Las Vegas metropolitan area.  They play in the Pacific Division of the Western Conference in the National Hockey League (NHL).  They have played at T-Mobile Arena since their inaugural season in 2017–18.  The Golden Knights joined the NHL as an expansion team in 2017.  The team's first head coach, Gerard Gallant was hired on April 13, 2017.

Marc-André Fleury: Marc-André Fleury (born November 28, 1984) is a French-Canadian professional ice hockey goaltender playing for the Vegas Golden Knights of the National Hockey League (NHL).  Drafted out of the Quebec Major Junior Hockey League (QMJHL) first overall by the Pittsburgh Penguins in the 2003 NHL Entry Draft, Fleury played major junior for four seasons with the Cape Breton Screaming Eagles, earning both the Mike Bossy Trophy as the league's top prospect and the Telus Cup as the top defensive player in 2003.  He joined the Penguins in 2003–04 and has won three Stanley Cup championships with the team in 2009, 2016, and 2017.  Internationally, Fleury has represented Canada twice as a junior, winning back-to-back silver medals at the World Junior Championships in 2003 and 2004.  He won a gold medal with Team Canada at the 2010 Winter Olympics in Vancouver.

1970 NHL Expansion Draft: The 1970 NHL Expansion Draft was the second expansion draft of the National Hockey League (NHL).  The draft was held on June 10, 1970, a day before the 1970 NHL Amateur Draft.  The expansion draft was held to allow the Buffalo Sabres and Vancouver Canucks to acquire players for the upcoming .

List of Vegas Golden Knights draft picks: This is a complete list of ice hockey players who were drafted in the National Hockey League Entry Draft by the Vegas Golden Knights franchise.  It includes every player who was drafted, regardless of whether they played for the team.  The Golden Knights franchise was founded as an expansion team in Las Vegas, Nevada in 2017.

1995 NBA Expansion Draft: The 1995 NBA Expansion Draft was the tenth expansion draft of the National Basketball Association (NBA).  The draft was held on June 24, 1995, so that the newly founded Toronto Raptors and Vancouver Grizzlies could acquire players for the upcoming .  Toronto was awarded an expansion team on September 30, 1993, while Vancouver was awarded the league's 29th franchise on April 27, 1994.  They were the first NBA teams based in Canada since the Toronto Huskies.  In an NBA expansion draft, new NBA teams are allowed to acquire players from the previously established teams in the league.  Not all players on a given team are available during an expansion draft, since each team can protect a certain number of players from being selected.  In this draft, each of the twenty-seven other NBA teams had protected eight players from their roster, and the Raptors and the Grizzlies selected fourteen and thirteen unprotected players respectively, one from each team.  Prior to the draft, the league conducted a coin flip between the Raptors and the Grizzlies to decide their draft order in this expansion draft and in the 1995 NBA draft.  The Grizzlies won the coin flip and chose to have the higher pick in the 1995 Draft, allowing the Raptors to receive the first selection and the right to select fourteen players in the expansion draft.

Supporting paragraphs: 2017–18 Pittsburgh Penguins season 2017 NHL Expansion Draft
Answer: June 21