Veseyans Rugby and Sports Club has been given the go-ahead by Walsall Council to keep the structure at its facility in Little Hardwick Road, Streetly.
Bosses said the loss of the marquee would have a huge negative impact on the teams and the community as there was no space within the clubhouse for strength and conditioning training to take place.
It has been in use at the venue since March 2017 but needed permission to remain at the site.
The club, which has 489 players across a host of teams, erected the marquee to carry out such training but had to gain planning approval as the facility is based in green belt land.
Fortunately for Veseyans, officers agreed the structure did not cause any harm to the surrounding area and have allowed the marquee to stay in place.
The club said age groups of players range from toddlers to seniors aged 50, representing Veseyans in a number of teams. They added it continues to grow and thrive.
Agents Rob Duncan Planning Consultancy said: “Veseyans Rugby Club was originally founded in 1927 and moved to their current site at Little Hardwick Road in 1955.
“They have grown to become an important and thriving local sports club. The club currently runs a number of teams which collectively provide sporting opportunities over a wide range of age groups.
“The marquee provides a valuable and essential facility for the club, enabling them to provide for the strength and conditioning of their players, and also to provide an indoor training area for use during inclement weather and by the youngest age group teams, and to provide other fitness opportunities.
"The club plays a highly valuable role in facilitating participation in sport within the borough.
“The recent growth of its mini-junior section is particularly important, as it has helped to encourage regular participation in sport from a young age.
“The facilities within the marquee are a key component of that growth."