Eddie Nketiah struck a fine goal as the English Premier League returned after the World Cup break to show that Gabriel Jesus's injury need not derail Arsenal's title bid, while Mohamed Salah picked up where he left off as Liverpool dispatched Aston Villa.
There was trembling in North London when Jesus went down in some discomfort, clutching his right knee, in Brazil's 1-0 World Cup defeat by Cameroon.
The summer recruit from Manchester City has been one of the main reasons why Mikel Arteta's side has mounted such a convincing title challenge, contributing 10 goals and assists combined in his first 14 league matches for the Gunners to fuel their unlikely championship aspirations.
Yet he now faces an indefinite spell on the sidelines, following surgery, denying Arsenal their most consistent source of goals as the fixtures continue relentlessly.
Heartbreak for one player regularly means opportunity for another in football, and Nketiah -- who penned a new deal at Arsenal during the summer -- now has a glorious chance to prove he can be the club's leading man.
The 23-year-old made little secret of his frustrations at the club last season, playing second fiddle to Pierre-Emerick Aubameyang then Alexandre Lacazette as Arteta gave him only rare and brief chances to prove himself.
Nketiah appeared primed for the exit door -- a free transfer to Crystal Palace was mooted -- before eventually committing his future to the club and signing a five-year deal.
Despite this, and presumably assurances about his role at Arsenal, he's been a bit-part player at the Emirates Stadium during the impressive early months of the season, not starting a single Premier League game and failing to score as well before the FIFA World Cup break.
Nketiah scored goals in the UEFA Europa League and in the Carabao Cup, but he was largely a peripheral figure as Arsenal roared to the summit of the Premier League table.
The Boxing Day visit of West Ham United was a prime opportunity for him to prove his class, and he seized the moment by scoring the hosts' third goal after the Hammers had initially taken the lead.
One goal does not prove Nketiah can replace Jesus, of course, but this was the finish of a player whose confidence doesn't appear to have been dimmed by his substitute role as he picked up a pass from Martin Odegaard, rolled Thilo Kehrer delightfully, and finishing emphatically beyond Lukasz Fabianski.
Arteta has been working with Nketiah behind the scenes -- his technical ability, his movement, his finishing -- and this goal encapsulated some of the improvements he's made under the Spanish coach.
"It was a great goal but I think overall his performance was incredible," Arteta told Arsenal's official website. "The way he understood the pressing, his intensity, the way he counter-attacked certain spaces, the composure he showed... and then he stayed patient. In the box he produced a moment of real quality to win us the game."
Nketiah has scored 11 goals in his past 11 home starts for Arsenal -- from just 16 shots on target; now he must prove he can shoulder the burden of being the club's leading man, and their great hope for goals as they look to maintain their assault on the title.
"Obviously Gabby [Jesus] is going to be a big miss, but you could see I'm so happy for Eddie," Bukayo Saka told Amazon Prime.
"I feel like we all believed in him; that's all he needs, us to just keep supporting him. He got his goal and that will give him a lot of confidence, so we just need to keep encouraging him."
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Nketiah, who rejected Ghana's advances to join the Black Stars ahead of the World Cup, was swamped by his teammates in raucous celebration after his goal.
"It was really nice," Nketiah said of his first league goal of the season, "but I think I enjoyed the celebration more, just seeing how happy my teammates were for me.
"They've seen how hard I work, and their reaction was amazing. It shows the real togetherness of the team when everyone celebrates like that."
Unlike Nketiah, Mohamed Salah hasn't found minutes -- or goals -- hard to come by in the Premier League in recent months.
Salah received criticism during the early part of the campaign, when he appeared still to be in his post-Africa Cup of Nations flunk, but he began to sharpen up again in front of goal from mid-September.
He had a hand in 13 goals in 13 games in all competitions leading into the World Cup break, and as one of the most high-profile stars to sit out the tournament must have been champing at the bit when domestic action returned.
After netting in the Carabao Cup defeat by Manchester City last week, he was the Reds' star performer as they dispatched Aston Villa on Monday.
Salah opened the scoring in the fifth minute with a sharp close-range finish after excellent interplay between Trent Alexander-Arnold and Andy Robertson, and later set up Virgil van Dijk from a corner for the Merseysiders' second 32 minutes later.
The Egyptian's opener took him level in the Liverpool goal charts with Kenny Dalglish -- still revered as "The King" at Anfield, and arguably the Reds' greatest ever player -- on 172 goals for the club. It hasn't gone unnoticed that the Scot took 515 games to register that many goals, while Salah has achieved the feat in just 277 outings since signing from AS Roma.
"It's crazy," Klopp said of Salah's record-equalling goal haul. "When you are mentioned in the same phrase or same sentence as Sir Kenny Dalglish then you did something right."
Salah's assist was his 50th in the top flight -- Steven Gerrard, another darling of Merseyside, is the only other Liverpool player to surpass 50 goals and 50 assists for the club in the Premier League -- while no other Reds player has scored more than his 55 goals away from Anfield in the history of the competition.
Perhaps he hasn't yet quite hit the heights he managed at the tail end of 2021, but we are still witnessing truly remarkable numbers from Salah.
In the English League Championship, Anass Zaroury made an immediate impact as he returned to action with promotion-chasing Burnley.
He was a late arrival in the Morocco camp for their remarkable World Cup run -- he was only included in the Atlas Lions' squad as a last-minute replacement for injured Amine Harit -- and saw action only as a substitute in the third-place playoff against Croatia.
But the 22-year-old needed only 50 seconds to get back among the goals after returning to club action.
He was named in Vincent Kompany's starting XI only 10 days after Morocco's World Cup adventure ended, and, within a minute of kickoff, set the Clarets on their way to a 3-0 victory over Hannibal Mejbri's Birmingham City with the fastest goal in the Championship so far this season.
"I don't think the normal mortal human being will understand the challenge there is to go on a bus tour in front of millions of people in your country and then turn up the next day and still do your job as if you have not done anything yet in your life," Kompany said of his young winger.
"As long as he keeps doing that, the sky is the limit. It's a terrific way to come back."
In Saudi Arabia, there was a showdown between two of Africa's top strikers of the past decade as Vincent Aboubakar's Al Nassr -- heavily linked with Cristiano Ronaldo since his departure from Manchester United -- squared off with Al Hilal and Odion Ighalo.
Both players made their mark on the contest, with the Nigerian opening the scoring for Al Hilal after 10 minutes before Aboubakar set up Talisca for a 56th-minute equaliser.
The two title contenders shared the points in a 2-2 draw that leaves Al Nassr in top spot on 23 points, while Al Hilal are fourth with 21.