(Photo credit: Bill Streicher-Imagn Images)

Harris English may have to face the next two critical tournaments in the United Kingdom without his caddie, Eric Larson, whose decades-old prison sentence has proven a tough hurdle to overcome amid new travel regulations for Americans visiting the U.K.

While Harris is in the U.K. for the next two weeks for the Scottish Open and the Open Championship in a bid to play in the Ryder Cup, Larson has been stuck trying to get an exemption to the new Electronic Travel Authority visa rules, which can refuse entry if an applicant has served 12 months or more in prison.

Larson spent 10 years and three months in prison before being released from a halfway house in June 2006 after pleading guilty to sending friends cocaine. He was reportedly not a drug user or big-time dealer.

After his release, Larson worked for Mark Calcavecchia, who reportedly helped him get back on his feet. Larson has since caddied for Anthony Kim in 2008, Jeff Overton in 2010 and English for the last eight years, including the last four years with English at The Open Championship.

English, who only learned of Larson's plight three weeks ago, has been working hard to help Larson earn passage to the U.K., including reaching out to Warren Stephens, the U.S. Ambassador to the U.K.

'It's just a matter of the right people seeing it,' English said. 'I didn't understand how complicated the process was. Someone could see this guy had something in his past 30 years ago, he's been fine the last 20. How long does this stay with him?'

In the meantime, English, who is No. 19 in the world and 10th in the U.S. standings for the Ryder Cup, had been using caddie Joe Etter, who currently works for Davis Thompson who is not playing in the Scottish Open. However, Etter will be needed in Northern Ireland with Thompson nabbing the final spot in the field for the Open Championship next week at Royal Portrush.

'Joe was my Plan B,' English said. 'Now we're going to have to get a new Plan B.'

English is still holding out hope that Larson will somehow be able to make it to the U.K. given the effort by multiple outlets to vouch for Larson's credibility.

'They (U.S. Ambassador Stephens' office) wrote a letter. The R&A wrote a letter. The PGA Tour wrote a letter. A charity event Eric works for in the States wrote a letter. It's not for a lack of effort,' English said. 'I think it could be sitting on someone's desk at the government somewhere.'--Field Level Media