Shawne Merriman says the Chargers knocked it out of the park with their Jim Harbaugh hire ... telling TMZ Sports he believes his ex-team now has a feeling of, "'Hey, we can go out and win a championship now!'"
The former pass rusher was fired up when we spoke with him shortly after the Bolts named the ex-Michigan coach their new head man ... explaining to us he thinks L.A. is now a real-deal Super Bowl contender.
Merriman says the roster Harbaugh is inheriting is "the most talented team to never make the playoffs" .