Martin O'Neill believes Hearts will still be a threat in the Scottish Premiership title race despite seeing his Celtic team beat their rivals 7-1 at Celtic Park on Sunday.

Celtic moved four points clear of Rangers at the top of the table with a dominant display, with Callum Osmand, Benjamin Nygren and Camilo Duran all starring for the hosts. 

Kieran Tierney and Nygren had Celtic two goals ahead by the 10th minute before Osmand netted twice in two minutes to almost put the result beyond a disjointed Hearts side. 

Laurent Mendy pulled one back for Hearts just before half-time, but Celtic's four-goal cushion was restored before the interval when Jamie McCart turned into his own net. 

Duran put Celtic further clear four minutes after the restart, with Nygren scoring his second and Celtic's seventh in the 83rd minute to add even more gloss to the scoreline. 

Celtic have now won 15 of their last 16 league games (L1), scoring two or more goals in 12 of those. Since the start of April, no other side has won 10 or more matches in the top flight. 

Hearts are already eight points behind Celtic just one season after losing the title on the final day against the Hoops, and O'Neill expects them to go close again in 2026-27. 

"Hearts will still be strong," O'Neill insisted. "They've got some really good players out there playing.

"They'll still be a big challenge for us and Rangers, obviously. Four points at this stage of the season is absolutely nothing."

Beautiful Sunday #CELHEA | #CelticFC https://t.co/gpnb3Rn0F7

— Celtic Football Club (@CelticFC) October 18, 2026

Celtic's triumph comes at a crucial time ahead of their Europa League clash with Celta Vigo, having failed to win their first two matches against Benfica and Ferencvaros. 

They have lost their last three European matches, conceding three or more goals in all three games (12 in total). The Bhoys have only lost four in a row within a single season once before, doing so in the 2017-18 Champions League.

Celtic and the LaLiga side met in the 2002-03 UEFA Cup, with Thursday's hosts progressing on away goals after a 2-2 aggregate draw (1-0 home, 1-2 away defeat).

And O'Neill said that changes would be made from their win against Hearts when they welcome Celta to Parkhead as they aim to get their European campaign up and running. 

"We'll make a couple of adjustments on Thursday, but we still want to try and win," O'Neill added.

"Other players coming on and getting little bits of games here and there as well helps immensely, helps the whole squad and I think it helps the confidence of the team.

"It'll be a tough game for us [against Celta Vigo]. They're very, very decent. It's a game we probably have to win. We'll go all out to try and do it."