Iowa has signed coach Kirk Ferentz to a six-year contract extension through the 2025 season.

Ferentz, who is in his 18th season leading the Hawkeyes, will see his salary jump to $4.5 million per year under the new deal announced Tuesday.

Ferentz’s last contract, which was for 10 years at roughly $40 million, was set to expire in 2020. Ferentz’s massive buyout was subject to scrutiny under his previous deal, but a 12-2 season capped with a trip to the Rose Bowl quieted that talk.

Ferentz and Oklahoma’ Bob Stoops are the nation’s longest-tenured coaches, having been hired within days of each other in 1999.