• Hero: Lopez tied a career high with six RBIs that included his grand slam, an RBI double and a run-scoring groundout.
• Figure this: Ken Griffey Jr. tied Harmon Killebrew on the home run list with his 573rd homer, leaving him 10 behind Mark McGwire. He also passed Ernie Banks into 19th place on the career RBI list (1,637).
• Quotable: "I love hitting here. You hit balls here that there's no way they're going to go out in Washington." -- Lopez
-- ESPN.com news services
Nationals 8, Reds 4
CINCINNATI (AP) -- Felipe Lopez has another reason to love the place.
The shortstop had the greatest year of his career at Great American Ball Park in 2005, when he hit a career-high 23 homers and made the All-Star team with the Cincinnati Reds. In his homecoming with the Washington Nationals, he had another grand moment.
Lopez hit a grand slam in the eighth inning Tuesday night, rallying the Nationals to an 8-4 victory over the team that traded him away last July.
He sure misses Cincinnati's homer-friendly park.
"Oh, of course," Lopez said. "I love hitting here. You hit balls here that there's no way they're going to go out in Washington."
Lopez and outfielder Austin Kearns were part of an eight-player deal between the teams last July 13, one the Reds now dispute. The Reds filed a grievance over the trade this month, contending that Nationals general manager Jim Bowden failed to fully inform them of reliever Gary Majewski's sore shoulder during the trade talks.
Bowden was sitting behind the Nationals dugout Tuesday, wearing sunglasses, when his end of the bargain came through.
Lopez connected for his third career grand slam off left-hander Jon Coutlangus (2-1), snapping a 4-all tie. His drive to left-center landed in the Reds' bullpen, one that could use someone like a healthy Majewski.
Lopez also had an RBI double and a run-scoring groundout, matching his career high with six RBIs. Washington's eight runs were a season high.
"It's a special night, whether it's here or anywhere else," Lopez said.
Like many of his teammates, Lopez was in a slump when the Nationals got to town, batting only .239 with a pair of homers. His big game Tuesday was long awaited.
"It's very important for him," manager Manny Acta said. "He's been struggling lately. He has been putting some good at-bats together, and tonight he had several."
Jesus Colome (4-0) took over in the seventh inning and got the win, Washington's eighth in 12 games. It was a reversal of the series opener Monday night, when the Reds rallied for three runs in the eighth inning and an 8-7 win.
Ken Griffey Jr. tied Harmon Killebrew on the home run list with his second in two games, but couldn't lead the Reds to their first back-to-back wins of the month. Griffey's two-run shot off left-hander Matt Chico matched Killebrew at eighth on the list with 573 homers, trailing Mark McGwire by 10.
He also leapfrogged Ernie Banks into 19th place on the career RBI list. Griffey has driven in 1,637 runs. Next on the list is former Reds first baseman Tony Perez at 1,652.
"He's swinging the bat as well as anybody in baseball," manager Jerry Narron said. "I'm not surprised. I'm sure he'll continue it."
David Ross also had a two-run homer for Cincinnati, which has lost 15 of its last 20.
Cincinnati's bullpen couldn't support a start by right-hander Kirk Saarloos that surpassed expectations. Saarloos made his first start of the season in place of Eric Milton, still bothered by a sore elbow.
Saarloos hadn't gone more than two innings during any of his 20 relief appearances this season, and hadn't pitched in eight days. He gave up six hits in 5 1-3 innings, turning a 4-3 lead over to the bullpen after his stamina was tested by 78 pitches.
Saarloos had another thing going against him. He came down with a virus that's been going around the clubhouse, and stayed home Monday to rest.
"I was kind of lightheaded," he said. "I think that benefited me. I didn't try to do too much, just throw strikes. Maybe when you're not feeling great, you don't put expectations on yourself."
Chico remained winless on the road this season -- 0-4 in five starts with a 6.31 ERA. He gave up only three hits in 5 2-3 innings Tuesday, but two of them were homers by Griffey and Ross.
Nationals LF Ryan Church was out of the lineup for the second straight day because of a sore left forearm. He was hit by a pitch from Baltimore's Erik Bedard on Sunday. The arm bothered him when he hit off a tee. ... Griffey's 10 homers are one shy of Adam Dunn for the team lead. He has hit eight of his homers since manager Jerry Narron moved him back to his accustomed spot at third in the order May 3. ... Griffey made a diving catch in right field to rob Kearns in the fourth inning. ... OF Josh Hamilton went on the 15-day DL with an upset digestive system. He's scheduled to see a specialist Wednesday.