The Swiss midfielder, who is appearing at his fourth World Cup, said the squad is full of confidence and eager to make a strong start against the reigning Asian champions in Santa Clara.
Speaking ahead of the match, Xhaka stressed that while tactics remain important, enjoying the occasion is equally vital.
"In football we always talk about tactical things, but you also have to enjoy the moment," Xhaka said. "One of the most important things is that you go on the pitch and feel free."
The 33-year-old said Switzerland's players are determined to represent their country and families with pride.
"We just want to bring our A game tomorrow," he added. "We want to perform for Switzerland and for our families. Tomorrow we will take the first big step. This is going to be the best World Cup."
Xhaka also underlined the squad's readiness for the challenge ahead.
"We are now impatient. We are primed and ready. We are physically ready, we are mentally ready."
Switzerland are competing in their sixth consecutive World Cup, a record matched in Europe only by France, Spain, England, Portugal and Germany. Despite that consistency, the Swiss have often fallen short in the knockout stages, exiting in the round of 16 in five of their last six World Cup appearances. Their most recent quarter-final appearance came in 1954.
A victory over Qatar would move Switzerland to the top of Group B after Bosnia and Herzegovina and Canada played out a 1-1 draw on Friday.
Head coach Murat Yakin believes his experienced squad is well equipped to make an impact. Seventeen members of the current team also featured at the previous World Cup, where Switzerland suffered a heavy last-16 defeat to Portugal.
"Two thirds of the players in my team have already played in a major tournament," Yakin said. "We learned our lessons from the past. Four years later, we have more experience. We do things better."
Switzerland will face Qatar, Bosnia and Herzegovina, and Canada during the Group B stage as they aim to turn experience into their deepest World Cup run in decades.
