Houston Rockets owner Leslie Alexander donated $4 million to the Hurricane Harvey Relief Fund started by Houston Mayor Sylvester Turner, the team announced.

"Our hearts are heavy seeing the devastation that so many of our friends, family and neighbors are experiencing," the Rockets said in a statement.

The Houston Astros ownership group also agreed to donate $4 million to the relief efforts.

Jim Crane, the ownership group and our Foundation will donate $4 million to the relief efforts aiding the victims of Hurricane Harvey. — Houston Astros (@astros) August 29, 2017

The donations were among several pledged by teams and athletes to aid victims of flooding in Houston, including a $50,000 pledge by Rockets point guard Chris Paul to Texans defensive end J.J. Watt's online fundraiser.

Paul's donation pushed the total raised by the fundraiser to $500,000. The total raised had increased to $1 million by Monday night, prompting Watt to raise the fundraiser's goal to $1.5 million.

The generosity of @CP3's $50k donation is actually what put us over the $500k mark. Phenomenal stuff from donations both large and small. — JJ Watt (@JJWatt) August 28, 2017

Now classified as a tropical storm, Harvey has devastated the Houston area with flooding as a result of unprecedented rainfall totals.

Among other donations announced:

The Texans and owner Bob McNair donated $1 million to the United Way of Greater Houston Flood Relief Fund. The NFL Foundation said it would match the $1 million donation, and New England Patriots owner Robert Kraft and his family pledged to match all funds donated to the American Red Cross in support of Harvey flood relief up to $1 million.

Major League Baseball also contributed to the cause, joining with the players' association to donate $1 million to the Red Cross and relief organizations chosen by the players.

St. Louis Cardinals first baseman Matt Carpenter, who is from the Houston area, said in a tweet that he will donate $10,000 to relief efforts for each home run he hits for the rest of the season.

Buffalo Bills defensive end Jerry Hughes, a native of the Houston area, told ESPN's Josina Anderson he will donate $25,000 to relief efforts and an additional $5,000 for each sack he makes this season.

The Associated Press contributed to this report.