Update 11/19/2020 2:24pm:

The Golden State Warriors' Klay Thompson has suffered a season-ending Achilles tear, according to ESPN's Adrian Wojnarowski. The star guard underwent an MRI Thursday morning after injuring his right leg during a workout the day before.

Reports say Thompson was playing with other NBA players when he felt pain in his calf area after landing on his right leg. The 30-year-old missed the entire 2019-2020 season after tearing the ACL in his left knee during the 2019 NBA Finals.

Based on the type of tear, Thompson is expected to make a full recovery.

Source: ESPN

Update 11/18/2020 11:34pm:

After several reports and rumors circulated on Twitter regarding the extent of Klay Thompson's injury, primarily that the multiple-time champion suffered a torn Achilles. The Golden State Warriors have expressed "fear" that Thompson sustained a "significant" Achilles injury. NBC Sports reporter and Warriors expert Monte Poole tweeted, "Klay Thompson's leg injury looked bad, according to two sources, but neither was ready assume catastrophic. The Warriors have significant decisions to make tonight/this week, so fingers are crossed as they wait." 

ESPN's Ramona Shelbourne wrote via Twitter, "Klay Thompson is having an MRI on his lower leg tomorrow morning. Everyone in Warriors land is very down, but hoping for the best. He felt pain in his lower leg—calf area— when he landed on it." She noted further, "Several members of the Warriors organization are headed down to LA to be there with Klay when he has his MRI," adding, Very hard night for Golden State. They were so excited to draft James Wiseman. But right before the draft they get word of a potentially devastating injury to Klay.

Original 11/18/2020 8:28pm:

According to reports, Warriors' guard Klay Thompson sustained a lower leg injury that has basketball fans alarmed. NBA insider and writer for Undefeated Marc J. Spears tweeted that a reputable league source said it's "not good." ESPN's Adrian Wojnarowski reported that Thompson is set to undergo testing within the next couple of days to determine the severity of the injury. 

This is unwelcomed news for Warriors fans who haven't seen Klay since he tore his ACL in the 2019 NBA Finals against the Toronto Raptors. This potential setback is a gut-punch to Golden State who expected to have "The Splash Brothers" back on the floor for the 2020-21 season. 

Source: espn.com