Elkeson and Gao Lin were on target as Marcello Lippi's men left the Korean capital with a 2-2 draw – and two vital away goals – following the first leg of the continental showpiece a fortnight ago.
Guangzhou's unbeaten home record in this year's tournament adds to the strength of their position still further ahead of the return clash, and they head into the match in a rich vein of form, having thrashed Wuhan Zall 5-0 to round off a third consecutive league title triumph last weekend.
Adding the continental prize to their trophy cabinet would make Guangzhou the first Chinese team to win the competition in its current format, while former Juventus and Italy manager Lippi is aiming to become the first man to guide teams to both AFC and UEFA Champions League glory.
Although Seoul also head into the match on the back of a victory, the form book does not point so favourably towards the visitors coming out on top at Tianhe Stadium.
Their come-from-behind 2-1 K-League win over Suwon Bluewings was Seoul's first win since overcoming Iran's Esteghlal in continental action – a run spanning six matches.
Dejan Damjanovic scored a brace to secure the points and it was the Montenegrin's late leveller in the first leg of the final against Guangzhou that ensures honours are still even at the halfway stage.
Experienced Seoul defender Cha Du-ri, who missed the first-leg of the final after being shown yellow cards in both legs of the semi-final against Esteghlal, claims that the triumph over the Bluewings has given his side plenty of confidence.
"We played Suwon in one of the biggest matches in K-League and we won and we have a lot of good energy before the second leg," he said.
"I believe we can win the second leg and become champions of Asia."
He added: "We did our best in the first leg and it wasn't a bad result as Guangzhou are a good team.
"Every away match is not easy to win, but we are confident and we have good energy."
