Omar Guardiola is set to join Nelson Suburbs clubmate Kristian Gibson in blue and gold this season.
A 22-year-old forward, Guardiola will boost the team's firepower in its frontline.
''He's a good all-round attacking player, good in the wide areas,'' Southern United CEO Chris Wright said.
''I think he's going to cause some problems for the other teams, so hopefully a bit of excitement too.''
Originally from Colombia, Guardiola has lived in New Zealand for the past decade and attended Marlborough Boys' College.
Now living in Blenheim, he is going through the process of seeking New Zealand citizenship.
Having been scouting the Mainland League for players who might have fallen through the cracks in Canterbury and Tasman, Southern coach Paul O'Reilly liked what he saw in Guardiola.
He trained with the team and both parties left impressed with what they saw.
''He's excited about the challenge; he wants to prove himself in the national league,'' Wright said.
''So we can offer him a challenge and in the national league.
''We're happy that he's committed to it. We think he's going to be great for the team.''
Operating with a low budget meant attracting top players to the region was a challenge.
However, an emphasis had been put on creating a quality environment for players to train, develop and play.
That had impressed both Guardiola and Gibson and Wright said it was good to see that reputation was starting to build.
Goal-scoring was an issue last year - the team managed just 20 in its 18 games.
While Guardiola looks to be a player who will help that, Wright said improving the overall squad, rather than just one area, remained the key goal.
''What we want to do is make sure that the overall team is strong.
''So by strengthening that squad it gives us more opportunity to score and we can spend more time in the opposition's half.
''So the aim is to score more goals and concede less.''
Guardiola had been on the cusp of the national league for the past couple of seasons, having earned a trial with Canterbury United in 2015.
It was announced earlier this week former Southern United striker Eric Molloy has signed with Team Wellington.
The Irish striker was Southern's leading goal-scorer last season, although the club opted not to re-sign him for the upcoming season.
