LOS ANGELES -- When the Dodgers were building their roster this offseason, they were thrilled about the top three in the lineup. Mookie Betts, Freddie Freeman and Will Smith make up one of the best three-headed monsters in the Majors, and they haven’t disappointed this season.

But as the Dodgers looked to round up the rest of the lineup, they salivated at the opportunity of adding J.D. Martinez, a three-time Silver Slugger and five-time All-Star, to hit behind their trio of stars.

Also not disappointing thus far in his first season in Los Angeles is Martinez, as the 35-year-old is currently riding a 14-game hitting streak, which was capped off with a two-run homer to help the Dodgers beat the Nationals, 9-3, on Tuesday at Dodger Stadium.

“Feels like I’m in a rhythm right now at the plate,” Martinez said. “Just happy we’re winning and it’s our lineup. I keep talking about it, but it’s a potent lineup up and down.”

Freeman also went 4-for-5 with a homer, extending his hitting streak to a Dodgers season-high 19 games. During his hitting streak, Freeman is 35-for-77 (.455), with five homers and 12 doubles. Jason Heyward also chipped in with a solo homer and Max Muncy and Betts each collected two hits.

But the biggest hit of the night came off the bat of Martinez. With the Dodgers holding on to a one-run lead in the seventh after six strong innings from Tony Gonsolin, Martinez gave Los Angeles some breathing room with a two-run homer to straightaway center field. That helped open the floodgates, as the Dodgers scored five runs over the final two innings.

“It was just consistent one through nine,” said Dodgers manager Dave Roberts. “Obviously, J.D. with the big homer two nights in a row, and then Freddie gave us a little bit of distance with his homer. All in all, really positive.”

Adding Martinez was a tough decision by the Dodgers. Martinez was an All-Star last season with the Red Sox, but his production at the plate cooled off in the second half, when he posted just a .701 OPS over his last 58 games.

The Dodgers, however, felt confident they could help Martinez, especially with a chance to reunite with hitting coach Robert Van Scoyoc, who has been really good friends with the designated hitter for quite some time. Martinez and Betts also maintained a strong relationship from their time together in Boston.

While the Dodgers took a chance on Martinez, including letting longtime infielder Justin Turner walk in free agency, the veteran Martinez also took a big gamble on himself. He accepted less money and fewer guaranteed years in free agency just to sign with the Dodgers.

Martinez’s start to the season was a bit shaky, however, as he had a .231 batting average through 17 games. He has admitted that he was “trying too hard” to impress his new teammates and organization. Martinez even played through a back injury that worsened and forced him to miss three weeks.

Since returning, Martinez has shown exactly what he’s capable of in a lineup where he doesn't have to be the premier attraction. Martinez has recorded a hit in 16 of the 17 games he’s started, including his current 14-game hitting streak. During the streak, Martinez has seven homers and 21 RBIs, and for the season he leads the National League with a .610 slugging percentage among hitters with at least 160 plate appearances.

“He’s been doing it for a long time,” Freeman said. “It’s fun to watch someone who is so into trying to perfect his craft. He’ll be the first one to tell you that at the beginning of his career he was trying to figure things out -- and he figured it out, and he’s keeping it as long as he can. … [I'm] glad the Dodgers signed him this past offseason."