Guess it's okay to let 'em see you sweat after all.

Ryan Phillippe and Amanda Seyfried proved they're still together, despite some baby drama for Phillippe, on Wednesday -- going for a couple's jog in the Hollywood Hills.

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The duo, who began their on-and-off relationship in October, remained mum on the subject of Alexis Knapp, the pregnant actress who claims to be carrying Phillippe's child.

Knapp, 21, and Phillippe, 36, dated for several months last year before the actor pulled the brakes on the relationship in September.

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The Lincoln Lawyer actor "doesn't know if he's the father," one source told Us. "If it's his, he'll take responsibility."

Amidst the drama, Phillippe apparently has the support of Seyfried, 25 -- and his famous ex-wife Reese Witherspoon, mother to his daughter Ava, 11, and Deacon, 7.

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"Reese has been really supportive," another insider says. "She knows that Ryan is a good dad and she respects that."

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