WBA "regular" welterweight champion Lucas Matthysse is a week away from the biggest fight of his entire career, when he faces eight division world champion Manny Pacquiao at Axiata Arena in Malaysia on July 15 [July 14 in America].

The 35-year-old Argentinean puncher is not concerned with Pacquiao's southpaw stance, which gave numerous top fighters a lot of trouble over the years.

“We’ve had a great camp and the only difference is I’m getting ready to face a southpaw like Manny Pacquiao. Otherwise, I’m very happy to be in Malaysia and I’m also happy because the fight is near,” Matthysse told the Malay Mail.

Pacquiao, 39-years-old, has a lot of pressure to look good in the fight.

The Filipino superstar is coming off a twelve round unanimous decision loss to Jeff Horn from July 2017 in Brisbane, Australia.

Most experts believe the boxer is at the end of his pro run - with no victories insides the distance since stopping Miguel Cotto in 2009.

He's also taking this fight without the services of his trainer for the last 16 years, Freddie Roach.

Earlier this year, Pacquiao parted ways with Roach. And instead Pacquiao is using his assistant trainer and best friend Buboy Fernandez.

Matthysse is taking no chances, he's expecting to fight the very best version of Pacquiao.

“He fought the best of his level during those four defeats so let’s not underestimate him,” Matthysse said.

Matthysse's head trainer, Joel Diaz, has worked hard in camp to get his fighter ready for Pacquiao's southpaw attacks.

“We’ve been focused on the southpaw stance. Even giving him southpaw sparring partners. Myself and Matthysse’s brother-in-law Mario Narvaez are both southpaws and we’ve been hitting the mitts against him ahead of this fight against Pacquiao,” Diaz said.

The biggest issue for them to overcome, says Diaz, is the big time difference.

“We’re trying to program him to train at the time he is fighting (about 11:30am). He’s been training in California really well and I want him to focus on the fight it’s a big fight,” Diaz said.