Lincoln boss Danny Cowley was left to reflect on what could have been as the Imps' historic FA Cup run came to an end.
With the score at 0-0, winger Nathan Arnold had their best chance in the first half as he cut inside to force Cech into a decent save.
Despite restricting the Premier League side to limited chances before Walcott's opener, Cowley believes his side should take inspiration from their first-half performance and took time to pay tribute to their fans who made the trip.
"I think we have to take a lot from our performance, particularly the first 45 minutes," Cowley said.