Youth from around Italy turned St. Peter's Square into a giant playing field on Saturday as they ran relays, played basketball and performed karate on a day dedicated to the celebration of sports.

As the Pope arrived in the overflowing square participants welcomed him as their "captain." He thanked them for the honor.

"As captain I urge you not to block yourselves off in defense, but to come on the offense, to play together our match, which is that of the Gospel," he said May 7.

"Sports in the community can be a great missionary tool, where the Church is close to every person to help them become better and to meet Jesus Christ," he told the enthusiastic crowds.

Pope Francis arrived in the early evening to witness performances of ballet and gymnastics. He also met with popular Italian sports figures and heard testimonies from those whose lives has been impacted positively by sports.

At one point, he met with members of an Italian amputee soccer team and posed for a group shot with one member's iPhone as the theme song from the 1981 movie "Chariots of Fire" rang out over the square.

The Pope's remarks focused on how sports can bring about good in the lives of young people. He noted that sports are like school and work in helping youth develop themselves and avoid addictions to drugs and alcohol.

He said that to belong to a sports team "means to reject all forms of selfishness and isolation--it is an opportunity to meet and be with others, to help each other, to compete in mutual esteem and grow in brotherhood."

The pontiff acknowledged the "beauty" of team sports which do not allow for individualism.

"In my country," he recounted to the youth, "when a player plays only for himself, they say, 'this one wants to eat the ball!'"

Everyone who wants to join in sports should be welcomed, he said, "not just the best, but everyone, with the advantages and limitations that everyone has, indeed, focusing on the most disadvantaged, as did Jesus."

He encouraged the young athletes to apply themselves in "the game of life" as they do in sports.

"Put yourselves in the game, in the search for good, in the Church and in society, without fear, with courage, and enthusiasm."

"Don't content yourselves with a mediocre 'tie.' Give the best of yourselves, spending your lives for that which is truly valuable and that which lasts forever."

Pope Francis closed his remarks asking for prayers that he would be able to "play in the game" of life "until the last day when God calls me to himself."

Saturday's event was organized by the Centro Sportivo Italiano, on the occasion of its 70th anniversary.