Montero joined the Swans in July 2014 – not long after playing at the World Cup – from Mexican club Morelia for an undisclosed fee.
The Ecuadorian international wideman, who is renowned for his exceptional pace, signed a four-year deal.
He impressed in his debut season at the Liberty, making 22 starts for the Swans in the club’s record-breaking Premier League 2014-15 campaign. He scored one goal and chalked up seven assists.
At the end of the season he featured in Ecuador's Copa America campaign, which saw them exit at the group stage.
Montero made 24 appearances – scoring once – in 2015-16 as the Swans finished 12th in the Premier League, then played 14 times during an injury-hit 2016-17 season.
Montero, who helped Ecuador reach the Copa America quarter-finals in 2016, signed a contract extension later that year which ties him to the Swans until 2020.
Made a number of telling cameo appearances during the 2018-19 season, before being loaned to West Brom in the January of that campaign.