METAIRIE, La. -- Fresh off the best season of his NFL career -- and heading into the final year of his contract -- New Orleans Saints running back Mark Ingram has been suspended four games for violating the NFL policy on performance-enhancing substances.

Ingram, 28, will miss games against the Tampa Bay Buccaneers, Cleveland Browns, Atlanta Falcons and New York Giants. He will be eligible to return to the Saints' active roster on Monday, Oct. 1.

Ingram will be eligible to participate in all offseason practices and preseason games.

The veteran running back is scheduled to earn a base salary of $4 million in the final year of his contract, meaning he will forfeit nearly $1 million -- and possibly more in bonus money -- by missing the four games. The suspension could prove even more costly if he was angling for a lucrative contract extension before the season kicked off.

In the meantime, second-year pro Alvin Kamara will take on an even bigger role in the Saints offense after being named NFL Offensive Rookie of the Year. Ingram and Kamara made league history in 2017 by becoming the first backfield teammates to each surpass 1,500 yards from scrimmage.

Ingram made his second Pro Bowl by running for a career-high 1,124 yards and 12 touchdowns. He also caught 58 passes for 416 yards.

Kamara took on a slightly larger share of the workload down the stretch last season -- which could remain the norm even when Ingram returns. However, it was expected to remain a 1A/1B situation after that worked out so well last year for the NFC South champions.

Ingram's Great 2017 Mark Ingram ranked in the top five last season in rushing yards, yards per rush and rushing TDs: Totals Rank Rushing attempts 230 13th Rushing yards 1,124 5th Yards/rush 4.89 4th Rush TDs 12 2nd

It's unclear who will be next in line in the Saints backfield after Kamara. Last year, undrafted rookie Trey Edmunds made the roster as a special-teams player and also carried the ball nine times for 48 yards and a touchdown. The Saints also have a more experienced backup, Jonathan Williams, on the roster. And they just drafted Louisiana Tech's Boston Scott in the sixth round. So that competition will be worth monitoring this summer.

Ingram, a former Heisman Trophy winner at Alabama and a first-round draft choice in 2011, got off to a slow start in the NFL because of nagging injuries, inconsistent production and an overcrowded backfield. But he has emerged as a true leading man over the past four years in New Orleans, including back-to-back 1,000-yard rushing seasons.

He has 5,362 rushing yards, 1,428 receiving yards and 48 touchdowns during his seven-year career.

He will be among several significant names to be suspended for the start the 2018 season due to PED violations. Cincinnati Bengals linebacker Vontaze Burfict, Carolina Panthers linebacker Thomas Davis, Los Angeles Chargers defensive tackle Corey Liuget, Oakland Raiders offensive lineman Vadal Alexander and free-agent quarterback Mark Sanchez received suspensions earlier this offseason.