That anxiety, though, was followed by relief as the Gunners held on, strengthening their belief they will hold a slender advantage when the teams reconvene for this Carabao Cup semi-final second leg at the Emirates Stadium in two weeks time.
By then, Wenger will be back in his usual place in the dugout having served his three-game touchline ban. He will be free to display the emotion he was forced to contain last night.
Antonio Conte had no such constraints and the Chelsea manager was given plenty of reasons to demonstrate his displeasure as his side spurned a succession of good chances to win the tie.
The Italian was even reduced to making a television gesture towards the end following a late penalty appeal, imploring referee Martin Atkinson to call on the VAR system.
The match official was in communication with his video assistant and decided there was no cause to change his view that Danny Welbeck’s challenge on Cesc Fabregas had been fair.
“I didn’t know the VAR referral was for that incident,” Welbeck said. “We could have nicked a goal but we look forward to the second leg.”
Conte had selected a strong side while the presence of Sanchez on the bench together with the absence through injury of Mesut Ozil — Wenger confirmed before the game the player had seen a specialist about a knee injury —and Laurent Koscielny meant that, on paper at least, Arsenal looked to be weakened.
That appeared to be confirmed during the opening 20 minutes although Chelsea had little to show their early territorial dominance.
Alvaro Morata was hoping to put his misfiring performance at the Emirates Stadium last week behind him when the striker’s failure to convert three good opportunities was a major factor in Chelsea’s failure to collect three points. But when the Spaniard was given an early chance to make amends, he could only shoot into the side netting when a pull back to the unmarked Danny Drinkwater might have produced the opening goal.
Wenger remained unmoved in the press box as his side struggled to assert themselves. Slowly, though, they began to gain ground and they created the best of the early chances when Jack Wilshere floated a pass over the Chelsea backline and into the path of Alexandre Lacazette.
The France forward had time to steady himself but instead opted to fire off a shot quickly and the effort never looked like troubling Thibaut Courtois.
Lacazette might have wasted the opening but the chance gave Arsenal more belief. Yet while Wenger’s side demonstrated more confidence going forward, they continued to appear vulnerable particularly down the left where the combination of Rob Holding and Ashley Maitland-Niles struggled to contain the forward runs of Victor Moses.
Twice the Chelsea wing-back cut inside and delivered powerful left-foot shots that David Ospina, the Arsenal keeper, struggled to deal with.
Arsenal pressed forward when they could and Alex Iwobi, selected despite Wenger having insisted the player would be punished after being photographed in the early hours at a party 36 hours before Sunday’s FA Cup defeat at Nottingham Forest, forced a save from Courtois after collecting Antonio Rudiger’s poor clearance.
There was a distinct sense that the two sides were playing with caution at the start of the two-legged tie but Chelsea should have reached half-time ahead when Cesar Azpilicueta floated a ball into the Arsenal box. It was the kind of delivery that has brought a number of goals for Morata this season, only this time Cesc Fabregas was on the receiving end, and the midfielder’s tame header was directed straight at Ospina.
If Chelsea had been shadow boxing during the first half, the opening minutes of the second suggested the gloves were off. Conte’s side reappeared to demonstrate an urgency that had been missing before the break and N’Golo Kante was unlucky to see a powerful, goalward shot strike team-mate Andreas Christensen. Moments later, as Chelsea forced a succession of corners, Christensen had greater cause for regret as he headed over from close range after Marcos Alonso had flicked on Kante’s cross.
Alonso’s strength in the air was a telling factor and the Spaniard’s run towards the near post was again unchecked when he moved to meet Fabregas’s corner. Another flick fell this time to the feet of Morata who was unable to react when he should have turned home from close range. The sense that this was turning into another frustrating night for the Chelsea top scorer grew as Morata saw a shot saved and then lost control as he made a strong run forward.
It was a worse evening for Wilshere, however, with the Arsenal captain forced off early in the second half after injuring his ankle as he blocked Drinkwater’s attempted cross.
Arsenal, though, continued to hold on with Christensen again guilty of missing a good headed chance.
And, as Conte’s side began to run out of ideas, the visitors grew more comfortable although Welbeck’s rash challenge on Fabregas inside his own area did nothing for Wenger’s mood in the final minutes. But the Frenchman will have been content to bring the tie across London with parity maintained.
Courtois 6; Azpilicueta 7, Christensen 6, Rudiger 7; Moses 8, Drinkwater 6 (Willian 68,6), Kante 7, Fabregas 6, Alonso 7; Morata 5 (Batshuayi 86), Hazard 6 (Bakayoko 84).
Ospina 5; Chambers 5, Mustafi 6, Holding 6; Bellerin 6, Wilshere 7 (Elneny 56,7), Xhaka 6, Maitland-Niles5 ; Iwobi 5, Lacazette5 (Sanchez 65, 6), Welbeck 6.