It remains to be seen whether the three relievers the Nationals acquired before Wednesday’s trade deadline will bolster baseball’s worst bullpen, but one of them is poised to add some spice to what already figured to be an intriguing September series against the division rival Phillies.

After trading for Blue Jays right-hander Daniel Hudson and Mariners lefty Roenis Elías, General Manager Mike Rizzo closed a deal for another Seattle reliever: Hunter Strickland, best known as the guy who drilled Bryce Harper with a 98-mph fastball on Memorial Day in 2017 because he was upset that Harper crushed a pair of home runs off him in the National League Division Series . . . three years earlier.

The plunking prompted Harper to charge the mound and fling his helmet in the general vicinity of Strickland, sparking a brawl that ended former Nationals fan favorite Mike Morse’s career. Morse, playing for the Giants at the time, suffered a concussion after stepping between Harper and onrushing teammate Jeff Samardzija. Post-concussion symptoms sidelined Morse for the remainder of the season, after which he retired.

Rizzo took issue with the suspensions — six games for Strickland, four for Harper — that MLB handed down in the wake of the fight, and while he’s generally a proponent of players policing themselves when it comes to responding to perceived violations of baseball’s unwritten rules, Rizzo called Strickland’s decision to throw at Harper a “selfish act.”

“You could tell his teammates weren’t all that fired up about it,” he said the following week. “[Giants catcher Buster] Posey stayed back there till the fight was just about over. . . . If it’s for a team-worthy cause where you’re protecting somebody, or that type of thing, teammates are fine with it. But when it’s a selfish act because you couldn’t get a guy out, that’s where I think a line was crossed.”

“I don’t know why he’s still thinking about it," Harper said after the brawl of his two NLDS home runs off Strickland.

Strickland has since said that intentionally drilling Harper was a mistake, and Wednesday, Rizzo was praising the 30-year-old’s competitiveness.

“Love the attitude, the chip on his shoulder,” Rizzo said. “He’s a tough guy that brings it. You love him or you hate him, and he’s a National now.”

Strickland, who has been limited to four games this season with a Grade 2 lat strain and was activated off the injured list this week, missed two months last season with a fractured right hand after he punched a door following a blown save against the Marlins. He expressed remorse for that decision, too, writing on Instagram, “I am truly sorry that one split second, stupid decision has caused so much harm and now set me back from being out there with my team to pursue our goal.” The Mariners signed Strickland as a free agent in January.

In an Instagram post on Wednesday, Strickland said he is “beyond excited to join the Nationals and help bring a championship to D.C.” Washington’s path to the postseason includes a five-game series at home beginning Sept. 23 against Harper and the Phillies, who are a half-game back in the wild-card race.

Strickland and Harper have faced each other one time since the brawl, on June 10 of last season. Strickland was booed as he entered that game in the ninth inning at Nationals Park, but he retired Harper on a groundout en route to closing the Giants’ 2-0 win. Now it’s Harper who gets booed in D.C.

Love him or hate him, Strickland is a National now, and his next showdown with Harper could well come with a postseason berth at stake — or during the late innings of the National League wild-card game. (Please, Nationals, go ahead and assign the new guy Harper’s old No. 34.) Once Public Enemy No. 1 on Half Street, Strickland should hear more cheers than boos going forward, especially if his battles with Harper don’t end like they did in 2014. No one, least of all Strickland, has forgotten how those turned out.

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