Starter Germán Márquez and the Colorado Rockies agreed Tuesday on a five-year, $43 million contract extension, pending a physical, locking up the right-hander whose breakout second half helped fuel the Rockies to the 2018 postseason, league sources familiar with the deal told ESPN.

Márquez, 24, capped off one of the best seasons ever by a Rockies starter. He struck out 230 in 196 innings and finished with a 3.77 ERA, building on a solid 2017, his first full season.

Acquired in a 2016 trade from the Tampa Bay Rays for outfielder Corey Dickerson, Márquez parlayed an increased use of his slider after the All-Star break to smashing success. Over 14 starts, he punched out 124 in 93 innings with a 2.61 ERA and six double-digit strikeout games -- including four 11-strikeout games in September.

The deal covers the 2019-to-2023 seasons, but also includes a club option that could turn into a mutual option for the 2024 season.

The extension is the second-largest guarantee for a pitcher with two years of service, behind reigning American League Cy Young winner Blake Snell, who signed a five-year, $50 million this winter. Márquez's deal is close to Gio Gonzalez's five-year, $42 million extension from the Washington Nationals in 2012 that came with a pair of team options. Gonzalez's deal also covered four arbitration seasons, whereas Márquez's encompasses three.

Because Márquez was not yet arbitration eligible, the deal is perhaps most similar in structure to the four-year, $40 million extension New York Yankees starter Luis Severino signed earlier this winter. Severino is a year older than Márquez and was slated to hit arbitration as a Super 2 before signing the deal. The club option on his deal allows the Yankees to buy out one year of free agency.

Colorado guaranteed one free-agent year and has the opportunity to get a second if it picks up the option, which can turn into a mutual option if Márquez finishes in the top three in Cy Young voting two years. The deal also includes escalators for top-five Cy Young finishes. The latest Márquez will reach free agency is following his age-29 season.

Márquez is part of perhaps the best rotation the Rockies have put together in their 27-year history, with Márquez and left-hander Kyle Freeland -- whom they've also tried to sign to a long-term deal -- headlining it alongside Tyler Anderson, Jon Gray and Chad Bettis. In his first start Friday, Márquez held Miami to two hits and one run over six innings and struck out seven.

Márquez's deal will be the Rockies' second-biggest signing this winter after they agreed with franchise third baseman Nolan Arenado on an eight-year, $260 million contract extension.