'I felt the love' - how did Alcaraz look on winning singles return?

After a 139-day wait, Carlos Alcaraz is back to winning ways on the singles court.

The seven-time major winner walked on to Arthur Ashe Stadium on Monday to begin his US Open title defence after spending just over four months on the sidelines with a wrist injury.

And he delighted fans with his entertaining brand of tennis and infectious energy as he beat Russia's Roman Safiullin 6-4 6-4 6-4.

Alcaraz was forced to watch from the sidelines as rivals Alexander Zverev and Jannik Sinner lifted the French Open and Wimbledon titles this summer.

However, the Spaniard is finally back - and grateful to be competing again.

"I missed the crowd, the energy, the competition – I missed everything," a smiling Alcaraz said in his on-court interview.

"I'm just really, really happy that I was able to compete again."

Despite playing with a compression sleeve on his right arm, Alcaraz unleashed his trademark forehand with familiar ferocity. The whippy stroke accounted for the majority of his 28 winners against Safiullin.

"I felt great. I don't know how it looked from outside, but from inside, my feeling was that I was hitting normal," Alcaraz said.

"I was playing pretty normal, playing my style, and everything felt great."

Each of Alcaraz's winners was met with a clenched fist and celebratory cry of "vamos" - Spanish for "let's go" - towards his team on the side of the court.

The 23-year-old clearly enjoyed the occasion, smiling after points and, at one stage, singing along to a Michael Jackson song at the change of ends.

When he ended an intense rally with a sublime drop shot during his final service game, Alcaraz lifted his fist to the sky before pointing to his ear and waving his arms to demand more noise from the raucous crowd.

Former Wimbledon champion Pat Cash said on BBC Radio 5 Sports Extra that it looked as though "every little win" was celebrated by Alcaraz.

"What I really want to do is enjoy every time that I'm going to walk into the court, feeling the energy from the people," Alcaraz said.

"That's what I'm going do this tournament. The results, it's going to come after all.

"That's why I enjoyed so much today, and it wasn't a surprise for me, because I came here to enjoy."

Even though Alcaraz enjoyed his first-round match at Flushing Meadows, there are improvements to be made as he continues his comeback.

While he impressed with his forehand and delicate drop shots, his serve did not carry the threat it usually does.

The defending champion managed just two aces to five double faults - although he did land 68% of his first serves and won 66% of the points behind it.

"The serve is the shot I was struggling [with] the most," Alcaraz explained, although he added that a slower serve was an intentional tactic to catch Safiullin out.

"I'm going try to serve better. The point is going to try to serve normal, but it's a shot that I just always struggle [with].

"But it will be back, for sure."

Alcaraz did not look overly short of match fitness, but he admitted he had doubts before his encounter with Safiullin over his ability to compete over five sets.

"There were some doubts in the match, I'm not going to lie," he said.

"I've been thinking about 'am I going to last the best of five, am I going to last playing four sets, five sets?'.

"I need more matches under the belt to get again into the rhythm of the tournament. I'm pretty sure I'm going to get better and better every day."

There will be tougher tests than world number 99 Safiullin for Alcaraz, who will face Portugal's 72nd-ranked Jaime Faria next.

However, his path to the final does seem to have opened up considerably.

World number one Sinner is absent because of a knee problem, while 24-time Grand Slam champion Novak Djokovic suffered a shock first-round exit to Argentina's Mariano Navone on Sunday.

As the second seed, Alcaraz is on the opposite side of the draw to French Open champion and top seed Zverev, and the pair cannot meet until the final.

Meanwhile, French 10th seed Arthur Fils - viewed by many as a title contender after winning the Cincinnati Masters earlier this month - went out earlier on Monday as he lost to Stefanos Tsitsipas of Greece.

It means that the only top-10 player that Alcaraz can meet before the semi-finals is American Ben Shelton.

Shelton, who is one of several home players aiming to end their nation's 23-year wait for a men's champion, made a nervous start in his opening match before fighting back for a 1-6 6-1 7-6 (7-3) 6-2 win against Dutch opponent Tallon Griekspoor.