Baltimore totaled nine home runs in taking two of three from the sputtering Reds. Lee had gone nearly seven weeks without going deep before connecting on Friday and Sunday.
"It's huge. He's swinging the bat real well lately, probably as good as anybody on our team," Reynolds said. "He's a big guy in that lineup that we need to hit, and he's doing that."
The Reds left town after a lamentable series in which they gave up 17 runs in three games. All but five of those runs came as the result of homers.
"You miss location, especially in this ballpark, something bad is going to happen," Cincinnati manager Dusty Baker said. "No. 2, they got some guys over there heating up, namely D. Lee."
It's precisely what the Orioles have been waiting for since the beginning of the season. Their offense isn't built for speed, but they have plenty of guys with the power to poke the ball over the wall.
"You look one through nine and you've got six, seven guys that I feel are real hot right now, that are swinging it well," Baltimore starter Jeremy Guthrie said. "I think that's what we had intended going into this season. ... We hope that it goes on throughout the rest of the year."
The teams combined for 16 homers in the series, including 14 in the last two games. The Orioles hit only seven homers during a recently completed road trip in which they lost six of nine.
"You can't get a hit every time with runners in scoring position but a lot of times, that's the game," leadoff hitter Chris Heisey said. "It's how you hit with guys on base."
Baltimore went up 5-0 in the fourth when Lee hit a three-run drive and Reynolds sent a 1-2 pitch from Homer Bailey into the bullpen area in center field, an estimated 443 feet from home plate.
Bailey (3-2) was activated from the 15-day disabled list before the game after being sidelined for a month with a sprained right shoulder. The right-hander gave up five runs and nine hits in five innings.
Cincinnati closed to 5-4 in the sixth but could not complete the comeback.
Nick Markakis had three hits and drove in two runs for the Orioles, including a two-out single in the sixth that made it 6-4. Markakis has hit in 16 straight games and is 30 for 74 (.405) during that span.
Scott's home run off hard-throwing Aroldis Chapman gave Baltimore a three-run cushion.
Guthrie (3-8) allowed four runs, six hits and four walks in 5 2/3 shaky innings. The right-hander was 0-3 in his previous six starts.
Phillips launched Cincinnati's comeback with a solo shot in the fifth. In the sixth, Guthrie was pulled after giving up an RBI single to Heisey and walking Phillips. Clay Rapada walked Joey Votto to load the bases, and Jim Johnson walked Jonny Gomes and Fred Lewis to force in a pair of runs.
Drew Stubbs hit into a fielder's choice to end the inning. In the seventh, Phillips grounded out with two on and two outs.
The Reds were without slugger Jay Bruce, who was too sick to play.
"He didn't feel well (Saturday) night. Even worse as the night went on," Baker said of Bruce, who leads Cincinnati with 17 homers but hasn't connected since June 1.
Orioles RHP Jake Arrieta (right elbow inflammation) has been scratched from his scheduled start Wednesday against St. Louis. He last pitched on June 20, and the team wanted him to get in another bullpen session before returning. ... Phillips' homer was his first since May 14. ... Reynolds made two errors at third base, giving him a major league-high 18 for the season. The 18 errors matches his total for last season with Arizona.