A vital cog in the Spanish machine that swept to triumphs at the European Championship in 2008 and 2012 and the 2010 World Cup, Xavi has been suffering from a niggling hamstring problem in recent weeks.
With Tuesday's showdown against France in Paris looming, Del Bosque is unlikely to risk the 33-year-old against the Finns and will probably hand the job of dictating Spain's play to Andres Iniesta, Cesc Fabregas or Santi Cazorla.
"We are not going to say anything new here today about Xavi, we all know how important he is for Barcelona and the national team," midfielder Javi Garcia said at a news conference at Spain's training base outside Madrid on Wednesday.
"We hope he recovers soon and if he has joined up with us it means he is fit enough to play and help us in at least one of the matches," the Manchester City player added.
Spain and France, who drew 1-1 in Madrid in October, are level on seven points at the top of the group after three matches, with the world and European champions in first place thanks to a superior goal difference.
The Finland game at Sporting Gijon's Molinon stadium, as well as France's match against second-placed Georgia at the Stade de France on Friday, are seen as mere appetisers for Tuesday's clash.
However, Spain forward Juan Mata said it would be a mistake to underestimate Finland, bottom of the group on one point, and the players should focus fully on Friday's game.
"As the coach has told us, it would be wrong to start thinking about the France match because before that we have to win the game in Gijon," the Chelsea player said in an interview published by one of the team's sponsors.
"There are six extremely important points at stake that will help us towards our goal and hopefully achieve it," he added.
As well as the Xavi issue, Del Bosque will have to decide which of goalkeeping trio Pepe Reina, Victor Valdes and David De Gea will take the place of captain Iker Casillas, who is recovering from a broken hand.
Reina is the more experienced at international level, with 26 appearances to 11 for Valdes, but has only recently recovered from a calf injury.
De Gea has been called up for a second time but has yet to make his debut for the national team.
Finland coach Mixu Paatelainen is expected to pick an experienced line-up for his nation's seventh meeting with Spain.
The last time they met was in a 0-0 draw in a friendly in Helsinki in October 2007 and the Spanish have won four, drawn one and lost one against the Finns overall.
"We will not build any castles in the air, but we will make it very nasty for Spain to win," midfielder Teemu Tainio said on the national team's website (www.palloliitto.fi).
"We must keep the gaps between the lines tight," added defender Kari Arkivuo. "Maybe Spain might get nervous if they can't play in between those lines."
Spain: 12-Victor Valdes; 17-Alvaro Arbeloa, 15-Sergio Ramos, 3-Gerard Pique, 18-Jordi Alba; 14-Xabi Alonso, 16-Sergio Busquets, 6-Andres Iniesta; 21-David Silva, 7-David Villa, 10-Cesc Fabregas
Finland: 12-Lukas Hradecky; 22-Jukka Raitala, 4-Joona Toivio, 3-Niklas Moisander, 13-Kari Arkivuo; 14-Tim Sparv, 19-Alexander Ring, 10-Perparim Hetemaj; 7-Roman Eremenko, 8-Teemu Tainio; 9-Mikael Forssell