Celtics' roster flexibility is key to a potential dynasty

The Boston Celtics have seven players under a long-term contract. Brad Stevens has extended Derrick White, Sam Hauser and Jayson Tatum this summer, building on the extensions given to Jaylen Brown, Jrue Holiday and Payton Pritchard over the last 12 months. 

As such, the Celtics are firmly above the second tax apron. Current projections have them sitting $25 million over the threshold, with that number likely to rise in the coming years. Being a second-apron team comes with some stiff penalties.

If Boston remains over the apron at the end of the upcoming season, it will have a future first-round draft pick frozen. It is also unable to aggregate salaries in a trade and will not have access to the taxpayer mid-level exception.

However, according to ESPN's Tim Bontemps, it's those contract extensions that have given the Celtics cause for optimism. 

"If the Celtics were to subtract just one of the big salaries from their books moving forward, and replace it either with draft picks or players on inexpensive, rookie-scale contracts, it would quickly become very plausible for Boston to get below the second apron, giving the Celtics flexibility to continue adding to the roster," Bontemps wrote.