National Car Rental has announced a new sponsorship agreement designating National as the Official Car Rental Partner of the Boston Red Sox through 2021.

The Red Sox agreement marks National’s ninth MLB team partnership, which include official car rental designations with the Los Angeles Angels, Houston Astros, St. Louis Cardinals, New York Mets, Baltimore Orioles, Texas Rangers, Kansas City Royals, and Chicago White Sox.

“We have a passion for baseball and are proud to support our newest MLB team — the Boston Red Sox — as their official car rental partner,” said Rob Connors, vice president of brand marketing for National. “We look forward to being a part of the Boston fan experience and offering our Emerald Club members exclusive entrance to Fenway Park through a dedicated express gate.”

As part of its designation with the Red Sox, National will have in-stadium signage above the Green Monster outfield wall as well as behind home plate and will sponsor the new Emerald Club Express Gate, a dedicated entry line to Fenway Park — exclusively for ticketed Emerald Club Members and their guests.

National will also have a presence in the Royal Rooters Club — a premier space within Fenway that features a collection of Red Sox memorabilia — and will sponsor the National Call to the Bullpen during all regular season home games.

“National Car Rental has a history and connection with a number of baseball teams and we are thrilled they have expanded on that relationship by partnering with us,” said Troup Parkinson, Red Sox’s executive vice president. “Their focus on providing their customers with unique services was a focal point of our partnership, and we are pleased to be providing their Emerald Club members with a special express entrance to Fenway Park.”

As part of the agreement, National advertising will be featured in select radio and television broadcasts of home games and in each edition of Red Sox Magazine. Starting in 2018, Emerald Club Members will have access to Red Sox ticket pre-sales, and National will also be featured on ticket backs. The agreement also includes digital and social support.