Wanderers beat Oxford United 2-1 in the League One playoff final at Wembley Stadium on Monday to leap up to English football’s second-tier.
And the Liverpool boss was in touch with the 38-year-old Akinfenwa, who is a lifelong Liverpool fan.
“Hello big man, congratulations,” Klopp said in a video posted by Akinfenwa on social media.
“I’m pretty sure your whole life at least a Championship player and now finally, you are there.
— daRealAAkinfenwa (@daRealAkinfenwa)July 13, 2020
“Well done. Great, great victory. Even in these strange times, I hope you celebrate appropriately.”
Akinfenwa revelled in promotion after being written off four years ago.
“Four years ago I stood in front of you and I was technically unemployed,” Akinfenwa said. “The only person that can hit me up on WhatsApp this time is Klopp, so we can celebrate together.
“Life and football is about opinions, four years ago somebody gave an opinion about me. That was their opinion.
“I hope my story shows that the only opinion that matters is the opinion you have about yourself. I was lucky and blessed to find a manager and players who believed in me.”