Kilmarnock have completed the signing of Borja, with the Spaniard joining until the end of the season.
The former Alcorcon player had been on trial at Rugby Park but Killie were not able to sign him in time to face Inverness last weekend.
However, the 30-year-old may make his debut when Kenny Shiels' side host against Motherwell on Saturday.
"We need finishers but he is one that certainly I am pleased to get," said manager Kenny Shiels.
"He plays at the top of the midfield, the same as [former Kilmarnock player] Dean Shiels, so we are trying to get that creativity into the team.
"We will probably need a goalscorer to take the pressure off Paul Heffernan and Rory Boulding."
Last season's joint-top goalscorer Herrernan is unlikely to play until October or November after breaking his collarbone and Shiels is keen to add another striker to his squad.
"It would have to be someone we get on loan where it would be a case of no wages," he said.
"I'm looking for a European club that would pay the wages and see this as an academy for their 19-20-year-old players to learn the game, because we play a European game.
"So I'm hopeful we provide that for some of the European clubs and that might be appealing to them."
Kilmarnock's summer signings
- Borja, forward
- Rory Boulding, forward
- Jeroen Tesselaar, defender
Killie have opened their Scottish Premier League campaign with two draws and Shiels believes a goal threat is all that has been missing from his side.
"If we had that we could have won both games, but we have ended up dropping four points," he added.
"But we drew our first two games last season and you have to be very conscious of the fact that the season has only started, we are not ready, the teams we are playing are not ready.
"There was a bundle of draws at the start of last season and this season.
"The last three teams to come up to the Premier have drawn 0-0, it's an example of teams just not being ready."
Meanwhile, Killie midfielder Gary Fisher has been loaned out to Hamilton Accies until 1 January.