Xavi hailed "sensational" Dani Alves and tipped the full-back to have a big impact at Barcelona after making his second debut for the club on Tuesday.
Alves returned to Camp Nou on a free transfer last month following his departure from Sao Paulo in September over a contractual dispute.
The 38-year-old, who played 391 times for Barca in his first spell with the club, cannot be officially registered for the Catalan giants until the January transfer window.
However, the Brazil international was able to pull on the Blaugrana strip in Barca's exhibition friendly with Boca Juniors and played a full part in Saudi Arabia.
Alves impressed in the first half in particular but could not help his side overcome Argentine giants Boca, who went on to win the penalty shoot-out 4-2 after a 1-1 draw.
Xavi may not be able to call upon Alves competitively for another few weeks, but the recently appointed Barca boss is glad to have the veteran defender in his squad.
"His second debut is very positive for the team," Xavi said after the Maradona Cup match. "Everyone has seen he will help us a lot. He is a sensational player.
"He's a team player and has a lot of character and soul. He will do very well for us.
"He has shown what he can contribute both in defence and attack. He plays with a lot of intensity and his final pass makes a difference."
Questions were raised regarding the timing of the game, which was held in memory of the late Diego Maradona, who represented both clubs during his legendary playing career.
But Xavi felt it was a good opportunity to give certain fringe players a run-out, with Philippe Coutinho among those to feature from the beginning.
"Those who have played less, like Neto or Riqui Puig, performed at a very good level, as did all the youngsters," Xavi said.
"The conclusions I take from this game are positive. We lost on penalties but are happy. Losing on penalties is the least important thing – getting minutes is what matters."
Ferran Jutgla gave a much-changed Barca side the lead at King Saud University Stadium, but Exequiel Zeballos struck 13 minutes from time to take the game to penalties.
Xavi's side now turn their focus back to LaLiga matters with a home match against Elche on Saturday, before travelling to Sevilla three days later for their final game of a testing year.
Barca have been linked with Erling Haaland as they prepare for 2022 after the Borussia Dortmund striker's agent reportedly met with club president Joan Laporta.
Given the LaLiga side's well-publicised financial issues, however, a move for the in-demand Norway international seems highly unlikely next year.
"These are all hypotheses," Xavi said when asked about the recent transfer speculation. "We will see, because we depend a lot on the salary limit and on financial fair play.
"We are not in our best moment but we will try to strengthen the team and the reinforcement of Dani will also go very well for us. In all markets we would like to strengthen."