San Francisco’s Randy Johnson delivers against Washington. Johnson logged his 300th career victory in a 5-1 triumph Thursday in Washington.

Washington ? The emotions finally flowed for Randy Johnson when the final out was made.

A hug for his son, who was serving as batboy. Hugs for every teammate, plus a really big one for his manager. The game ball presented to his wife as his three daughters beamed with pride. A news conference that lasted a half-hour from a player who usually doesn’t have much to say. Someone even spotted a smile.

The Big Unit admits he can come across as surly, and he did his best over the past few weeks to downplay his pursuit of 300 wins. Once he got there — with a steady, six-inning performance in San Francisco’s 5-1 victory over Washington in the opener of a doubleheader Thursday — he was free to express that, yes, it really is a big deal.

“I think it kind of hit me when I walked on the field,” Johnson said. “It’s a long-range achievement.”

In the nightcap, the Giants completed a sweep with a rain-shortened 4-1 victory. The game was called with two outs in the top of the sixth after a delay of 67 minutes.

Johnson became the 24th pitcher to reach the 300-win milestone. He walked two, struck out two, allowed only an unearned run and threw 50 of his 78 pitches for strikes.