WASHINGTON -- Joe Panik was 3-for-4 with a walk and drove in two runs and Chris Stratton got his first major league win as a starter as the San Francisco Giants beat the Washington Nationals 4-2 in the first game of a day-night doubleheader Sunday.

Stratton (1-2), making his third career start and 13th game, struck out a career-high 10 batters with just one walk while going a career-best 6 2/3 innings. The 2012 first-round pick from Mississippi was 1-0 in seven games out of the bullpen as a rookie in 2016.

The Nationals had five singles and did not get anyone to second base against Stratton until the seventh. With two runners on lefty reliever Josh Osich retired pinch hitter Daniel Murphy on a flyball for the last out of the seventh. Sam Dyson pitched the ninth for his ninth save.

Gorkys Hernandez, the No. 8 hitter, had an RBI single in the second and two batters later Panik lined a single to drive in two runs and give the Giants a 3-0 lead against A.J Cole. Pinch hitter Kelby Tomlinson had a sac fly off Matt Grace in the eighth to make it 4-0.

Cole (1-3) gave up three runs in six innings before Sammy Solis took over in the seventh.

Hunter Strickland was roundly booed when he entered the game to pitch in the eighth for the Giants. Strickland hit Bryce Harper with a pitch in April to ignite a brawl in which both players were suspended.

Anthony Rendon then hit a two-run homer off Strickland to trim the lead to 4-2 after the Giants bullpen had not allowed an earned run in 21 1/3 innings. It is the first extra-base hit by a current National against Strickland in 22 at-bats.

Andrew Stevenson (2-for-4) got the start in center for the hosts. Regular center fielder Brian Goodwin (2-for-4) started in right in place of the injured Harper.

The first-place Nationals (69-46) began the day with a league-high team average of .275. The Giants (47-71) lost their first four games to Washington this season and last five overall. Ryder Jones and Hernandez had two hits for the Giants.

NOTES: Washington RF Bryce Harper (hyperextended left knee) went on the 10-day disabled list Sunday and OF Michael A. Taylor was recalled from his minor league rehab assignment with Double-A Harrisburg. Harper was injured in his first at-bat while running out a groundball late Saturday night but may not be lost for the season. "We dodged a bullet," said Washington general manager Mike Rizzo. ... The Giants called up INF Orlando Calixte from Triple-A Sacramento as the 26th man for the day-night doubleheader while the Nationals called on C Pedro Severino from Triple-A Syracuse for the same role. ... Giants manager Bruce Bochy has 1,836 career wins and Washington manager Dusty Baker has 1,835. ... Giants LHP Ty Blach (8-7, 4.15 ERA) will face Marlins LHP Adam Conley 4-5, 5.43 ERA) on Monday in Miami.