James has shone since quitting Real last July at the end of three often difficult seasons in Madrid for a two-year loan deal in Munich.
“Both games will be special for me,” James told Spanish newspaper AS before the first leg at the Allianz Arena.
“I was at Real for three years, I have friends there and good memories from that time.
“I’m only thinking about my team now and how we can beat Real.”
The Colombian had an impressive first season in the Spanish capital in the wake of a starring role for his country at the 2014 World Cup in Brazil.
However, the appointment of Zinedine Zidane as Madrid coach in January 2016 set him back, with the Frenchman not seeing James as a key part of his team.
Yet, while Zidane seemed relieved to see James leave the Santiago Bernabeu, his Real team-mates were not.
Last November, Cristiano Ronaldo publically pointed to the playmaker’s departure as a reason for Madrid’s erratic form this season.
In Munich, the 26-year-old attacking midfielder has rediscovered the form which saw him light up that World Cup and finish as the competition’s top scorer.
He came to Bavaria to work under Carlo Ancelotti, his first coach at Real.
The Italian was sacked in late September after a poor start to this season, but he has remained a popular choice under Ancelotti’s successor Jupp Heynckes.
Heynckes said the key to James’ development has been having the freedom to take risks.
“He realises that he’s allowed to make mistakes and that it’s not a reflection of his performance if he’s taken off,” explained the Bayern boss.
Encouraged to roam the space behind top scorer Robert Lewandowski, James also gives Bayern another potentially lethal option from dead balls.
– ‘Staying here’ –
Real’s loss has been Bayern’s gain.
James was part of two Champions League-winning teams with Madrid. He did not play in either the 2016 or 2017 final, but he knows exactly how Real tick in Europe.
“They use a different ‘chip’ in the Champions League than they do in the (Spanish) league,” he told Munich-based newspaper TZ.
“They manage to get the most out of themselves. They know what it takes to fight for this trophy year after year.”
Bayern have been knocked out of Europe by Spanish opposition in each of the last four seasons, including losing to Real in the quarter-finals last year.
They will hope James can help end that run. He has been described by Heynckes as a “godsend”, having scored six goals and provided twice as many assists so far this season.
He announced his arrival last September by capping his first league start by scoring and creating a goal in a 3-0 win at Schalke.
He did not look back, helping Bayern secure a sixth straight Bundesliga title. All that is missing is a statement performance in Europe — ideally against Real.
His loan spell ends in June 2019, but he was crystal clear when German magazine Kicker asked about his future.
“I’m staying here,” James said.
“My present is here and I’m very happy in Munich. I don’t want to think about anything else.”
Bayern chairman Karl-Heinz Rummenigge describes the 13 million euros ($15.9m) they paid to take James on loan as a “very, very good transfer.”
“We’re in no hurry. We have very clear conditions in terms of the contract,” said Rummenigge.
“We have a two-year loan deal and then a purchase option of 42 million euros that we will have to take up.”
James added: “Bayern is fantastic, I’m happy and I can imagine myself playing for many more years here.”
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