​SOUTHPORT, England (AP) — Jordan Spieth was four days shy of turning 24 when he delivered pure magic in the final hour at Royal Birkdale to win the British Open for the third leg of the Grand Slam. It was among the most astonishing finishes in a major championship.Perhaps even more astonishing? He has only two PGA Tour victories since. He has played in the final group at a major only once.AdvertisementAdvertisementAdvertisementWhat hasn’t changed is his optimism that he can get back to his best golf, now matter how far away that looks for a player who is No. 51 in the world, who has not been to the Tour Championship the past two years, who has not been in the conversation at a major in five years.“If you give up on reaching your ceiling, then I don’t see a point in playing anymore,” Spieth said Monday. “So for me it’s always about I’ll do everything I can to be trying to be at the very best in the world, because I know that I can be. I have been. It’s nice to have the blueprint.”The blueprint was nearly a decade ago — the pursuit of the calendar Grand Slam that ended with a bogey on the 17th hole at St. Andrews in 2015, his British Open title two years later, and playing in the final group at Carnoustie in 2018 as he tried to keep possession of the claret jug.He feels he is on the right track and keeps getting a bad hand. The analogy he used earlier this year was having a bad shoe at the blackjack table, staying put because as soon as he walks away, fortunes surely will turn.AdvertisementAdvertisementAdvertisementHe’s still at the table.“I’m quite frustrated with the results considering I know where my game is at,” Spieth said. “It’s better than it was four or five years ago when I got back to top 10 in the world. It’s without a doubt better than it was then. It’s just not quite showing up in results.“At the same time, it’s a stay-the-course mentality,” he said. “Sometimes you get rewarded right away, like I did back then maybe in a bit of a lucky fashion, and I understand that sometimes it’s delayed. And that’s how it feels like it is right now. … So I’m just waiting for that opportunity.”The return to Royal Birkdale at least allows him to remember how it felt to walk up to the 18th green with victory secure, sitting on the edge of a pot bunker with the claret jug as dozens of photographers captured the image of a 23-year-old often referred to then as “Golden Child.”AdvertisementAdvertisementAdvertisementWhat he can’t relive is the finish. He lost the lead on the 13th hole even though his bogey felt like stealing a shot — he took a penalty drop from a dune covered in high grass, hit a blind shot from the driving range and limited the damage with a chip-and-putt for bogey, just like always.Then came the 6-iron he nearly holed on the par-3 14th and the 50-foot eagle putt on the par-5 15th hole — “Go get that,” he famously said to caddie Michael Greller — and two more birdies.“Maybe the best sho