WASHINGTON - It's only April and once again Nationals manager Dave Martinez is trying to fix his bullpen.

The Washington bullpen struggled early last year in the team's first season under Martinez. And that subplot is back as the Nationals begin a three-game series at home Tuesday night with the San Francisco Giants, whose bullpen has been an early strength.

Washington (7-7) relievers have a 7.75 ERA - the worst mark in the National League - and the Nationals' overall ERA is 5.00, which is 11th. The Giants (7-10) have a league-best bullpen ERA of 1.77 and an overall mark of 2.75.

How little faith does Martinez have in his bullpen?

As of Monday, Nationals relievers had pitched a league-low 40.2 innings and given up seven homers. By comparison, Giants relievers have thrown 61 innings and allowed just one homer.

"We've got to see what we've got," an upset Martinez said after Sunday's 4-3 loss to the Pittsburgh Pirates.

Martinez was explaining his decision to go with Wander Suero in the top of the ninth on a day closer Sean Doolittle was not available due to his recent workload. And in effect the Nationals were down two relievers as Trevor Rosenthal (72.00 ERA) can't be trusted in a tight game.

Suero gave up an RBI double to Jason Martin for what proved to be the game-winning run in the top of the ninth. To make matters worse former Washington, reliever Felipe Vazquez of the Pirates retired hot-hitting Howie Kendrick and Anthony Rendon for the final two outs of the game with the bases loaded in the last of the ninth.

Kendrick is hitting .533 and Rendon is batting .400 with six homers and 17 RBI in just 55 at-bats.

"You got Howie up, and you got Rendon up. Both had good at-bats, we just couldn't get it done," Martinez said.

The Nats got eight innings from Max Scherzer on Sunday and will hope for more of the same from Stephen Strasburg (1-0, 5.40), who will face the Giants. The starter for the Giants will be Dereck Rodriguez (1-2, 4.15). He is the son of Hall of Famer Pudge Rodriguez, who was behind the plate for Strasburg's debut at Nationals Park in 2010.

Strasburg is 3-3, 3.77 in nine starts against the Giants while Rodriguez is 0-1, 16.88 in his only start against Washington - which came last year at Nationals Park.

While the Giants offense as struggled, outfielder Tyler Austin got good news Sunday on an MRI on right elbow came back positive.

"It's progressively gotten better," he told MLB.com.

The Giants played 18 innings at home Friday before winning in walk-off fashion against the Rockies. Backup catcher Erik Kratz caught all 18 innings in that game; he caught 18 innings for the Pirates in a game at Nationals Park in 2016.

San Francisco had just one hit in a loss at home Sunday to the Rockies.

The Giants have a league-worst team batting average of .199 while the Nationals are at .260.

"You've got to get those timely hits," Giants manager Bruce Bochy, who grew up in northern Virginia, told reporters. "This game's pretty simple."

--Field Level Media