Christian Eriksen was conscious and undergoing further tests in the hospital after collapsing during Denmark's friendly against Ukraine, which forced the game to be abandoned.
Eriksen, 34, appeared to grab his chest before falling to the ground in the 65th minute of the international fixture in the Danish city of Odense, with Norwegian referee Sigurd Smehus Kringstad calling the game off in the 79th minute due to the incident involving the VfL Wolfsburg midfielder.
"He was briefly unconscious, but regained consciousness very quickly," national team doctor Morten Boesen said in a Danish federation statement.
The former Manchester United and Tottenham player previously suffered a cardiac arrest and had to be resuscitated on the pitch during Denmark's Euro 2020 encounter with Finland in Copenhagen in June 2021.
Eriksen was subsequently fitted with a special heart-starting device known as an implantable cardioverter-defibrillator and, after being released by Inter Milan, was able to relaunch his playing career with Premier League team Brentford in February 2022, just eight months after collapsing against Finland.
Denmark and Ukraine players surrounded Eriksen while he was being treated. A hush fell over the crowd before a chant of "Eriksen, Eriksen" went around Nature Energy Park in Odense, Denmark.
National team doctor Boesen added: "Christian is doing well and walked off the pitch by himself. As I see it, the pacemaker responded as it should.
"He was briefly unconscious, but regained consciousness very quickly, and we were quickly in contact with him.
"He will now undergo further examinations at the hospital to determine what caused the incident. We are in ongoing contact with him and the doctors at the hospital.
"But Christian is doing well, and he asked me to send his regards to all the players and tell them that he was okay."
In a post to social media, Eriksen's club, VfL Wolfsburg, wrote: "We're thinking of you, Christian," adding that they were in close contact with the Danish federation.
"All the best and a speedy recovery," the post added.
On X, Tottenham wrote: "Our thoughts are with Christian Eriksen and his family. Wishing you a full and speedy recovery, Christian. We're all with you."
Manchester United, the club Eriksen left in 2025, also offered a message of support.
"Everybody at Manchester United is encouraged by Denmark's update on Christian Eriksen following today's abandoned friendly against Ukraine," a post on X read.
"The club is sending strength and love to Christian and the Eriksen family as we await further news."
Neither Denmark nor Ukraine qualified for the World Cup.
After the collapse against Finland in 2021, Eriksen's teammates stood around him in a wall, shielding him to protect his privacy.
After receiving medical attention for around 10 minutes, he was carried off on a stretcher.
The match was halted, and UEFA said both teams held an emergency meeting before deciding to continue the game. Finland went on to win 1-0, and Eriksen was named man of the match.
The midfielder is widely considered one of the greatest players in Danish football history. He began his senior career at Ajax before joining Tottenham, where he made 305 appearances, scoring 69 goals and providing 88 assists.
He joined Inter in 2020, then was without a club for eight months following his first collapse.
After a spell at Brentford, he spent three seasons at United before joining his current club, Wolfsburg.
Information from The Associated Press contributed to this report.