When someone is on a team they usually wear team shirts, use team gear and do team cheers. They like to represent their team and let others know that they're part of it.
As Christians, Jesus calls us to let our "light shine before men" rather than hiding His light under a shade and covering it. This doesn’t mean that we have to forcefully demand that someone become a Christian or go around telling people they're doing wrong all the time, but we should show Christ with our lives. We should live unashamed of being a Christian and never try to cover up the fact that we are followers of Jesus Christ.
Many Christians, including me, try to pray quickly in public so that no one will notice what they’re doing. I’ve done that many times when a player from the other team is injured. And when someone asks us why we’re not doing something that goes against the will of God, we often try to come up with other reasons, like telling our friends that our parents are "making" us miss the pick-up game of basketball to go to Bible study.
Jesus doesn't call us to shove our faith in people's faces, but He does want us to be honest about knowing Him. Today, don’t hide your role as a member of His team. Instead, live out your love for Him and don't be ashamed!