San Francisco 49ers legend Dwight Clark passed away on Monday at the age of 61 after a battle with amyotrophic lateral sclerosis (ALS). His wife, Kelly, shared the heartbreaking news via Dwight's official Twitter account.

"I'm heartbroken to tell you that today I lost my best friend and husband," she wrote. "He passed peacefully surrounded by many of the people he loved most. I am thankful for all of Dwight's friends, teammates and 49ers fans who have sent their love during his battle with ALS."

The 49ers organization issued the following statement following Clark's passing.

"The San Francisco 49ers family has suffered a tremendous loss today with the passing of Dwight Clark. We extend our condolences and prayers to Dwight's wife, Kelly, his family, friends and fans, as we join together to mourn the death of one the most beloved figures in 49ers history. For almost four decades, he served as a charismatic ambassador for our team and the Bay Area. Dwight's personality and his sense of humor endeared him to everyone he came into contact with, even during his most trying times. The strength, perseverance and grace with which he battled ALS will long serve as an inspiration to so many. Dwight will always carry a special place in our hearts and his legacy will live on as we continue to battle this terrible disease."

Former 49ers owner Eddie DeBartolo Jr. issued the following statement.

"My heart is broken. Today, I lost my little brother and one of my best friends. I cannot put into words how special Dwight was to me and to everyone his life touched. He was an amazing husband, father, grandfather, brother and a great friend and teammate. He showed tremendous courage and dignity in his battle with ALS and we hope there will soon be a cure for this horrendous disease. I will always remember Dwight the way he was — larger than life, handsome, charismatic and the only one who could pull off wearing a fur coat at our Super Bowl parade. He was responsible for one of the most iconic plays in NFL history that began our run of Super Bowl championships, but to me, he will always be an extension of my family. I love him and will miss him terribly. Our hearts and prayers are with his wife Kelly, his children and the entire Clark family."

NFL Commissioner Roger Goodell issued the following statement.

"All of us in the NFL are saddened by the passing of Dwight Clark. Dwight made many memorable contributions on the field as a two-time Super Bowl champion and later as a member of the front office of the 49ers and Browns. He will forever live on in our memories for The Catch but also for his kind, gentle and courageous spirit. We send our deepest sympathies and love to Dwight's wife, Kelly, his family, teammates, and the many people whose lives he touched, including mine, throughout his career and life."

News of Clark's battle with ALS broke in March of 2017. He started feeling weakness in his left hand in September of 2015 and went through months of tests before the diagnosis was made.

RELATED Bay Area icon and 49ers great, Dwight Clark, passes away

Clark played nine seasons with the 49ers after the team made him a 10th-round selection in the 1979 draft. During his time in San Francisco, he registered 506 receptions for 6,750 yards with 48 touchdowns during regular-season play. Clark also appeared in nine playoff games while adding 48 receptions for 726 yards with three touchdowns.

Clark was selected to the Pro Bowl twice (1981, 1982) and was a two-time All-Pro (1981, 1982). He led the NFL in receptions during the 1982 season and won two Super Bowls with the 49ers (XVI, XIX). For NFL fans, he was best known for "The Catch" against the Dallas Cowboys during the NFC Championship Game on January 10, 1982. The iconic play is viewed as the launching pad for a 49ers dynasty that would be a dominant force for nearly two decades. His jersey number (87) is retired by the 49ers and is part of the team's Ring of Honor.

The 49ers honored Clark during a regular-season game at Levi's Stadium on October 22, 2017. He, along with fellow legends Joe Montana and Jerry Rice, was at the game that Sunday. DeBartolo hosted a three-day gathering for Clark in April, which included former teammates, coaches, and staffers.

Another 49ers legendary receiver, Jerry Rice, shared the following via Twitter on Monday.

"Dwight was a vibrant charismatic soul!! Jennifer (Montana) and I are heartbroken over his passing," wrote Joe Montana via Twitter. "While we knew it was inevitably coming, it came way [too] soon! We are grateful for the decades of love and friendship we shared. We are praying for Dwight, his family and for all your prayers also. We will miss you dearly! Love Jennifer and Joe Montana."

Current 49ers players also shared their thoughts on the legend's passing.

General manager John Lynch posted the following.

NFL Network analyst Michael Silver shared his thoughts on Clark shortly after news broke of his passing. You can listen to what he had to say below.

Other members of the media also shared their thoughts on the sad news.

New England Patriots quarterback Tom Brady, who grew up a 49ers fan, posted the following via Instagram.

Dwight Clark was one of my idols growing up in San Mateo. I was lucky enough to be at the game where my hero Joe Montana perfectly placed the game winning throw/catch to Dwight in the corner of the end zone to beat the cowboys in the 1981 season. I was 4 years old and cried to my parents the entire first half because I couldn't see the field when the grown ups would stand and scream for the 49ers. I got a chance to meet him when we happened to share the same orthodontist in San Mateo and I sabotaged one of his visits just to meet him and shake his hand. He was incredibly gracious to me that day as a young boy. And I never forgot the impact he made on me as all of our heroes do. I am sad tonight hearing of his passing of ALS but I know he is now resting and at peace finally after many years valiantly fighting such a terrible disease. Thank you for the great memories and RIP! 🙏🏼

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