Atletico confirmed the former Chelsea striker as part of the 20-strong group which would travel to England in a post on the club’s official website and Twitter feed.
Costa had been taken off early in the second half against Sporting Lisbon on April 12 as Atletico went on to secure their place in the last four of the Europa League despite a 1-0 defeat, progressing 2-1 on aggregate.
Speaking ahead of Sunday’s LaLiga match against Real Betis, which finished goalless, Atletico manager Diego Simeone had suggested Costa stood “no chance” of being fit for the first leg of the European tie at the Emirates Stadium.
Arsenal, meanwhile, come into the game on the back of a 4-1 Premier League win over West Ham in what was the first match since manager Arsene Wenger announced he would stand down at the end of the season.
Costa scored for Chelsea against the Gunners in last season’s FA Cup final, which Arsenal went on to win 2-1.
— Atlético de Madrid (@atletienglish) April 24, 2018
Provided by Press Association Sport
With the veteran French coach set to step down after almost 22 years in charge at the end of the season, it will be all change at the Emirates Stadium this summer.
Here, we take a look at some of the key questions faced as part of Arsenal’s recruitment process.
Does experience really matter?
Wenger was an unheralded young coach when the former Monaco boss arrived at Highbury from Japanese side Nagoya Grampus Eight to take over the Gunners in the Autumn of 1996.
It would, though, be something of a surprise to see Arsenal go the same way again. Nevertheless, Gazidis, the man likely to give a final recommendation to majority shareholder Stan Kroenke, is said to favour former Gunners midfielder Mikel Arteta.
While already a popular figure, the Spaniard would bring limited first-team experience, having only just moved into coaching as assistant to Pep Guardiola at Manchester City.
The same can be said of former Gunners enforcer Patrick Vieira, cutting his managerial teeth with New York City in the MLS. Such an appointment would be a gamble, but then again, so is starting life after Arsene.
What do you do again?
With Raul Sanllehi installed as head of football operations and Sven Mislintat as head of recruitment, it appears increasingly likely there will no longer be a first-team manager in Wenger’s mould.
The added input of ideas, though, could also muddy the waters somewhat in terms of what exactly Arsenal are looking for in their ideal candidate. With his Barcelona connections, it is no surprise Luis Enrique has been among the leading contenders.
Julian Nagelsmann at Hoffenheim would fit the bill of a young, hungry coach, as would Domenico Tedesco at Shalke, both well-known to former Borussia Dortmund man Mislintat.
Whoever eventually comes in, though, will have to be able to work within a structure which would see a lot of the tasks from Wenger’s tenure delegated elsewhere.
How are you with numbers?
How Wenger managed to keep Arsenal competitive in the top four of the Premier League for so long without the resources afforded to his rivals was often both held up as sound accounting as well as a frustrating call to loosen the purse strings.
There is, though, unlikely to be a £100million warchest awaiting the new manager, head coach or whatever their title is. Still, expect plenty of moments during the summer – with under-performing players off-loaded and fresh talent brought in to help shape the new era.
Have you ever watched Arsenal Fan TV?
Wenger had become a divisive figure in recent seasons, something even he acknowledged after the first match since the announcement of his departure.
Everyone, of course, is entitled to their own opinion, whatever it may be – but one thing above all else will swiftly get the fans onside: winning. And 1-0 to the Arsenal would not be a bad place to start.
Former Chelsea forward Marko Marin was involved in a comical incident recently.
During a Greek Super League game between Olympiacos and Apollon Smyrnis, Marin dived after a slight push from the referee while trying to win a penalty that was denied in the first place.
Well, referee Alexandros Katsikogiannis wasn’t impressed and subsequently handed him a yellow card.
To add insult to injury, Marin’s Olympiacos side lost 1-0.