The Washington Nationals and star outfielder Bryce Harper agreed to a one-year deal for $13,625,000 on Friday, a source told ESPN's Buster Olney.

Harper will again avoid arbitration. He did so before the 2014 season by signing a two-year deal that paid him $5 million this past season.

The Nationals on Friday also reached deals with third baseman Anthony Rendon ($5.8 million), right-hander Tanner Roark ($4,315,000) and new catcher Derek Norris ($4.2 million).

In 2015, Harper became the youngest unanimous MVP ever after a season in which he hit .330 with 42 home runs and led the majors in on-base and slugging percentage.

But in 2016, the former first overall pick, who turned 24 in October, struggled to replicate his historic MVP campaign. In 147 games, he hit .243 with 24 homers and an .814 OPS that was nearly 300 points lower than a year earlier. During the second half of the season, when he missed five games in August with a shoulder injury, he hit just .226 with a .709 OPS.

The four-time All-Star selection finished the season with 86 RBIs as the Nationals won the National League East.

Still only 24, Bryce Harper is already a four-time All-Star and he was the NL Rookie of the Year in 2012. Thearon W. Henderson/Getty Images

Harper, who is represented by agent Scott Boras, has reportedly sought a long-term deal with the Nationals in excess of 10 years and $400 million. He is scheduled to become a free agent after the 2018 season.

He married his longtime girlfriend, Kayla Varner, this offseason.

Rendon is coming off a bounce-back year in which he hit .270 with 20 homers and a career-high 85 RBI while appearing in 156 games; injuries limited him to 80 in 2015. The No. 6 overall pick in the 2011 amateur draft, Rendon is entrenched as Washington's starting third baseman and made $2.8 million last season.

Roark was Washington's second-best starter in 2016, behind NL Cy Young Award winner Max Scherzer, going 16-10 with a 2.83 ERA in 33 starts, returning to the rotation after spending a year working out of the bullpen. He earned a substantial raise after making just under $543,300 last season. Roark ranked fifth in the NL in wins, sixth in ERA and ninth in hits per nine innings.

As of now, Norris is penciled in as the starting catcher for the Nationals, who acquired him in an offseason trade with the San Diego Padres. Norris is coming off a terrible 2015 at the plate: He batted only .186 with 14 homers and 42 RBI and a hard-to-believe .255 on-base percentage. He made $2,925,000 last season. Unless Washington goes out and adds another catcher, the 27-year-old would replace Wilson Ramos -- who signed with Tampa Bay as a free agent -- as the team's everyday guy behind the plate.