Barcelona enjoyed a fruitless pursuit of Brazil international Coutinho in the summer transfer window, with Liverpool rejecting a final bid from the Catalans that was believed to be in excess of 120million euros.
The 25-year-old has been reintegrated into the Reds' first team, having been out injured in the first part of the season while also being given some extra time to clear his head following the failed summer exit.
Many believe the Rio de Janeiro-born star will be subject of huge interest again at the turn of the year and Grau has now revealed Barca are more than ready to splash the cash on Coutinho in the next window.
"We are ready to buy Coutinho in the winter market, or any player the technical staff request," he said at a press conference. "But it is important to adjust ourselves, so if there are to be arrivals, there must be exits as well.
"We must forget about the price paid for Neymar last summer. After taxes we received about 188million euros in income and a direct financial impact on the club's treasury of 144million euros."