Sparks fly for Big Bang Theory's Johnny Galecki and his girlfriend at LA Lakers game

They've been dating since last year.

And things are clearly still going strong between Big Bang Theory's Johnny Galecki and his girlfriend Kelli Garner as the lovebirds were spotted smooching at Sunday's Los Angeles Lakers game.

The warmly-dressed actors could not disguise their obvious passion for one another, even in full view of 19,000 people at the Staples Center.

Basketball snuggles: Things are still going strong between Big Bang Theory's Johnny Galecki and his girlfriend Kelli Garner as the lovebirds were spotted smooching at Sunday's Los Angeles Lakers game

The Roseanne favourite, who at 37 is nearly a decade older than his ladylove, wore a grey wool vest over a blue dress shirt, blue jeans, and black boots.

With her blonde hair up in a top knot, the 28-year-old starlet flaunted her substantial cleavage in a long-sleeved black top, dark blue jeans, and black boots.

At one point, Johnny conscientiously wiped Kelli's mouth as she drank from a plastic cup of beer, and he could also be seen romantically kissing the back of her hand.

PDA: The warmly-dressed actors could not disguise their obvious passion for one another, even in full view of 19,000 people at the Staples Center

Romantic: The loved-up couple, who made their official debut at a pre-Oscar party in February, appeared to also thoroughly enjoy watching the Lakers get defeated by the Orlando Magic

The loved-up couple, who made their official debut at a pre-Oscar party in February, appeared to also thoroughly enjoy watching the Lakers get defeated by the Orlando Magic.

Other celebrities sitting courtside at the game included Ashley Tisdale, her best friend Samantha Droke, and her Scary Movie 5 co-star Regina Hall - wearing bizarre lace-up thigh-high boots.

As the affectionate couple displayed their PDA, a bored-looking Ashley seemed to be missing her 30-year-old boyfriend Scott Speer, who directed her in the 3D dance film Step Up Revolution.

Where's Scott? As the affectionate couple displayed their PDA, a bored-looking Ashley Tisdale seemed to be missing her 30-year-old boyfriend Scott Speer, who directed her in the 3D dance film Step Up Revolution

Star-studded: Other celebrities sitting courtside at the game included Tisdale, her best friend Samantha Droke, and her Scary Movie 5 co-star Regina Hall - wearing bizarre lace-up thigh-high boots

In the past, Galecki dated his Big Bang co-star Kaley Cuoco for two years, as well as actress Laura Harris and florist Kelsey Harper.

Meanwhile, amply-charmed Garner has also been linked to her Thumbsucker co-star Lou Taylor Pucci and Prometheus hunk Logan Marshall Green.

Aside from playing Leonard Hofstadter in the CBS sitcom now in its fifth season, the dark-haired actor will star alongside Topher Grace, Zachary Quinto, and Luke Wilson in next year's thriller called The Invitation.

Joaquin Phoenix lookalike! Johnny plays real-life record executive Terry Ork in next year's CBGB, which takes a look at the New York City punk-rock scene

Johnny also plays real-life record executive Terry Ork in next year's CBGB, which takes a look at the New York City punk-rock scene and the venerable nightclub of the same name.

Ashley Greene, Malin Åkerman, Alan Rickman, Justin Bartha, and Rupert Grint are also set to appear in the punk-infused flick.

Kelli, whose ABC series Pan Am was canceled last June, will next be seen in the film Horns, alongside Daniel Radcliffe, Juno Temple, and James Remar.

In the fantasy drama, due out next year, a young man awakens to magical horns sprouting from his temples after his girlfriend's mysterious rape and murder.

Big bang hit: Galecki currently stars as Leonard Hofstadter in the CBS sitcom Big Bang Theory, now in its fifth season