A romantic comedy like “The Switch” needs a fresh spin to survive the doldrums of late August. Accidental sperm donation, sadly, just isn’t enough.

Jason Bateman stars as Wally, a likable hypochondriac who has long felt romantic feelings for best friend Kassie, played by Jennifer Aniston. Unlucky-in-love Kassie decides to have a baby by way of sperm donor, and Wally isn’t too thrilled with the idea.

At at sperm donation party (odd), Wally gets drunk and, by means too absurd to describe, ends up switching the specimen. The next morning, he doesn’t remember a single thing about the incident.

Kassie moves away and seven years later returns to the city with the child in tow. Wally and the kid share some intense similarities, and Wally begins to remember details of the ol’ switcheroo.

Despite this sitcom-like setup, “The Switch” falls into the typical romantic comedy traps. The voice-over narration is abysmal, and the final act struggles through the same inane “misunderstandings” that cripple so many in this genre.“The Switch” powers through the tedium thanks to Bateman, the charming star of beloved sitcom “Arrested Development” who has since taken steady paychecks for amusing supporting roles in movies like “Juno,” “The Kingdom” and “Hancock.” He even makes the big father revelation into a powerhouse acting moment that belongs in a better movie.

Aniston is charming in what ultimately becomes a supporting role, and young Thomas Robinson hits all the cute notes as the uptight mini-Wally. Jeff Goldbum keeps things interesting by playing Wally’s best friend as the fumbling and bumbling Jeff Goldblum we all love.

While it doesn’t amount to much, the characters here don’t insult your intelligence like they do in many of this year’s rom-com entries, notably “When in Rome” and “Valentine’s Day.” “The Switch” is pleasant and only occasionally annoying. Good enough for late-August movie theater air conditioning… at matinee prices.

Grade: B-