As the world's No. 1-ranked men's badminton doubles tandem, Lee Yong-dae and Yoo Yeon-seong of South Korea will be carrying the weight of the nation when this year's Summer Olympics kicks off in Rio de Janeiro -- though that's not exactly why Yoo has been doing extensive weight training.

The 29-year-old only hopes to add to his power game -- defined by his formidable smashes -- that perfectly complements Lee's flair around the net and his defensive wizardry.

"I fully expect our opponents to come after us (at the Olympics)," Yoo said during the national team's open practice session in Seoul last Thursday. "We want to be as perfect in our preparations as we can be."

This is the one aspect of Yoo's game that Lee says he'd like to resemble the most. Lee, 27, has been the face of Korean badminton since winning the mixed doubles gold medal at the Beijing Olympics in 2008 -- his cheeky wink at the camera in celebration further catapulting him to stardom -- but he throws his pretty-boy image out the window once he's on the court. Lee is a hard-nosed type who will work for every point and who makes up for what his doubles partner may lack in defensive acumen.

"I'd love to learn how to hit smashes like Yeon-seong, because power is such an important part of the game today," Lee said. "The opponents will try to push me back because I am not a typical power player."

Lee has joined Yoo in the weight room to add power to his game, but Lee also understands his limitations and won't try to overextend himself.

"I'm not just focusing on brute force; I'm also working on sharp-angle shots," Lee said. "I will try to make my shots more difficult to return."

The two first became a team in October 2013. They rose to No. 1 in less than a year, by August 2014, and have stayed there ever since. They captured eight titles in 2015, including four in a row at one point.

The No. 2-ranked tandem from Indonesia, Hendra Setiawan and Mohammad Ahsan, are nearly 20,000 points behind on the world rankings, but they've been neck-and-neck against the South Koreans in recent showdowns.

The Indonesians claimed three out of five head-to-head matches in 2015. But in 12 meetings overall since Lee and Yoo became a team, the South Koreans remain ahead at 7-5.

Lee and Yoo have had a comparatively easier time against the third-ranked tandem Fu Haifeng and Zhang Nan of China. The South Koreans have beaten Fu and Zhang in their last four meetings, dating back to last August, and have a 5-2 head-to-head record.

Lee said losing to Setiawan and Ahsan in the final of the 2014 Asian Games on home soil in Incheon especially stung, and he hopes to take lessons from that defeat.

"I think we have a better sense of what it takes to beat them," Lee said. "They're such smart players around the net and have the quickness to boot. They deserve all the respect that they get."

Yoo said there's so little separation between his team and the Indonesians that, should they clash at some point in Rio, he and Lee will have to be perfect.

"We have to execute high-percentage shots," Yoo added. "We're trying to polish up our defense and net play."

As for the weight of heightened expectations at the Olympics, both Yoo and Lee are well-equipped to handle it with aplomb.

Though Lee is two years Yoo's junior, he is by far the more battle-tested and decorated player. Rio will be his third Olympics.

Yoo said he admires Lee's ability to deal with pressure and rise to the occasion.

"He has a wealth of big-game experience and he knows how to win," Yoo said. "He has a great understanding of how to manage his game. I must learn that from him."

Yoo has the "what, me worry?" outlook on the Olympics, and is talking himself into believing that the Olympics aren't any bigger than a regular event.

"Once I start thinking about the magnitude of the competition, I will grow more nervous," he said. "I will try to treat it like any other tournament, though I will obviously have to concentrate a little harder than usual."

Yoo also serves as a big brother figure and a voice of reason for Lee, who has long preferred older partners. Yoo is the one that keeps Lee composed when the younger teammate is about to get ahead of himself.

"As I've played more events with him, I've become more relaxed and confident," Yoo said. "I have to stay within myself to help Yong-dae do the same."

Heading into the London Olympics, Lee, then playing with Jung Jae-sung, was also at the top of the men's doubles rankings. The two cruised to the semifinals without dropping a set in four consecutive matches, but lost in the semifinals against Mathias Boe and Carsten Mogensen of Denmark despite taking the first set.

Lee recalled that he should have played with more poise after opening up the lead. He wants to erase that disappointing memory and feels he has just the right man by his side to do so.

"We have a very good understanding of what we both have to do to win," Lee said. "We're a great team and we've grown more confident after winning all those events last year. We'll try to be even better this year." (Yonhap)