Rafael Nadal and his long-term girlfriend were out to lunch in Melbourne on Thursday.

However Rafael, who is Down Under for the Australian Open, and his partner appeared tense throughout their meal at the upscale Nobu eatery.

The 32-year-old tennis champion and his 31-year-old girlfriend appeared to be having an animated exchange through the meal.

Maria Francisca Perello, also known as Xisca, placed her head in her hands at one stage while Rafael looked on with a tense expression.

The pair sat at a table with a bottle of water between them, both appearing glum and strained.

During lunch, Maria pointed what appeared to be a pair of green chopsticks at Rafael with her eyes wide at the athlete.

As the meal continued, the Spaniard continued speaking in an animated fashion, his hands raised.

During the exchange, Perello looked strained as she wiped her nose with a white napkin.

As her partner spoke, the business graduate looked less than impressed, holding what looked like edamame pod near her mouth.

The two left the restaurant together but appeared to keep their distance from each other as they walked.

The current world No.2 bit his lip as he walked, wearing a white sweatshirt, cap, and black shorts with Nike sneakers.

Maria wore a black and white sleeveless shirt, black shorts, and had a floral scarf wrapped around her neck.

Rafael and his Maria have reportedly been a couple since 2005.

Speaking to The Telegraph back in 2011, Maria said: ‘Even if my family asks me about Rafael, I prefer not to say much.’

‘The fact is that I just don’t feel comfortable talking about these things, even in private. It’s what works for me and what works for Rafael and me as a couple. We wouldn’t have it any other way.’