Magic Johnson just resigned from Square's board less than a year after joining

Magic Johnson, the NBA legend who has built a successful business life after basketball, has stepped down from the board of directors of Square.

In a letter addressed to Square CEO Jack Dorsey, Johnson said he was resigning to focus on a new development firm he launched to capitalize on President Obama's promise that the federal government will spend trillions on U.S. infrastructure upgrades over the next decade.

"Initially, I thought it would take some time to raise capital; however, my team and I were fortunate that the first investor we approached invested $1 billion," the letter read. "Within the 1st quarter of 2016, we have over $1.3 billion in our newly formed fund, [which] will require a significant and unwavering time commitment from me as I work to secure contracts around the country."

Despite the explanation, the resignation will still lead to some raised eyebrows, since Johnson only joined the board in the last year and Square has had a bumpy first six months as a public company.

Square is replacing Johnson with Paul Deighton, the former Commercial Secretary to the Treasury of the United Kingdom, who was previously a partner at Goldman Sachs. Square does not currently do business in the U.K.

This is the second Brit Dorsey has named to the board of a company he runs in the last few months; he recently named British entrepreneur Martha Fox to Twitter's board of directors.