Davis hails players' composure
Adam Dugdale headed the only goal of a game Crewe dictated for long periods before a late rally from the visitors failed to level matters.
The result extends Alex's unbeaten run to 17 matches ahead of Wednesday's return leg at Roots Hall - the last place Davis' youthful charges tasted defeat back in February.
"It's fantastic thing for the players," he said.
"They'll learn a lot from today having not been in this situation before .
"There's five or six of them that are in their first season in professional football.
"I've enjoyed the fact that we've played exactly how we did on our run. They played with confidence, they've been smiling, they enjoyed the atmosphere - they've soaked all that up.
"That's not easy for young boys to get through. It was a big contest between experience and youth.
"Now we've got to do it all again and that's going to be very hard. They'll be wounded so we've got to be ready for what they throw at us next week."
Davis, a defender in his playing days, was delighted to see centre-back Dugdale up from the back to find a superb finish from Ashley Westwood's 49th-minute free-kick.
"That's the way to win a game isn't it - a chip off the old block," he added.
"It was like something I'd seen back in my Burnley and Barnsley days.
"We've worked at those free-kicks. It was the fact that Duggy got there early and wanted the free-kick taking early before they could set up.
"I said to the players when we were practising set plays over the past two days was that they could be crucial to us if the games are very tight and both teams are cancelling themselves out."
Southend had effectively nullified the the hosts up until that point, but manager Paul Sturrock was clearly frustrated with a lacklustre performance that displayed few hallmarks of a team that took 13 points from their last five league matches.
Late opportunities fell to Michael Timlin, Bilel Mohsni and substitute Freddy Eastwood, but the U's now face an uphill task to remain in the hunt for a promotion that evaded them by a point in the regular season.
"We didn't really turn up until after half-time, said Sturrock.
"Them scoring a goal spurred us on a wee bit and we created three or four decent chances after that.
"I'm disappointed in our performance in the first half and over the 90 minutes I think 1-0 was a fair result.
"You've got to give credit to Crewe, they were up and at us right from the first minute.
"It took us a while to get into the game, but in the second half we started to get it right more around their box and started to get a rhythm going.
"Now we've got to hope our crowd get behind us and we get the result we need."
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