New York, Sep 10 (IANS): Spanish youngster Carlos Alcaraz made it to his maiden Grand Slam final, with the third seed battling past home favourite Frances Tiafoe 6-7(6), 6-3, 6-1, 6-7(5), 6-3 in four hours and 19 minutes to set up a winner-takes-all US Open clash against Casper Ruud of Norway on Saturday (IST).

Ruud moved past Russia's Karen Khachanov 7-6(5), 6-2, 5-7, 6-2 to reach his second Grand Slam final, further boosting his chances of rising to No. 1 in the ATP Rankings.

Alcaraz, who too is in line to become the new No. 1 should he win the summit clash, is the second teen to make the US Open final in the Open Era, joining the legendary Pete Sampras of the US.

"To be honest in the semifinal of a Grand Slam you have to give everything... we have to fight until the last ball. It doesn't matter if we are fighting for five hours, six hours. It doesn't matter. You have to give everything on court," Alcaraz was quoted as saying by ATP.

"Frances (Tiafoe) gave everything on court. This is amazing."

Alcaraz has now won three successive five-setters lasting a total of 13 hours and 28 minutes, and if the Spaniard wins the title on Sunday, he will become the youngest world No. 1 in the history of the ATP Rankings since 1973.

"It's amazing to be able to fight for big things. First time in the final of a Grand Slam. I can see the No. 1 in the world, but at the same time it's so far away," Alcaraz said. "I have one more to go against a player who is unbelievable. He deserves to play a final. He played the final of a Grand Slam in Roland Garros. This is my first time.

"I'm going to give everything that I have. I will have to handle the nerves of being in a final of a Grand Slam, but obviously I'm really, really happy and as I said before every match, I'm going to enjoy. I'm going to enjoy the moment and let's see what happens."

"I gave everything I had left tonight," Tiafoe said. "Too good Carlos, I am happy I got to share the big stage with you."

Earlier, Ruud moved past Khachanov, soaking up the 27th seed's powerful hitting and winning an epic 55-shot rally to win the first set.

Ruud, the fifth seed, who lost to Spanish stalwart Rafael Nadal in the French Open final, will become the first Norwegian to rise to No. 1 in the world if he defeats Alcaraz in the final.

"This match was another great match from my side," Ruud said.

"I think we were both a bit nervous at the beginning, a few breaks back and forth. But you have to take into account that this match is probably the biggest in both of our careers. Of course there will also be some nerves but I was fortunate to win that first set, which calmed my nerves a little bit.

"I played phenomenal in the second and Karen stepped up in the third. It was back and forth like every five-setter is, but I am just so happy. After Roland Garros I was extremely happy but of course humble enough to think that could be my only final at a Grand Slam in my career. It doesn't come easy, but here I am back again a couple (of) months later."

The 23-year-old had never gone beyond the third round in four previous appearances at Flushing Meadows.