Crewe boss Steve Davis has backed his young side to finish the job after they sealed a trip to Wembley in the npower League Two play-off final.
Leading Southend 1-0 from the first leg, goals from Ajay Leitch-Smith and 17-year-old substitute Max Clayton helped earn a 2-2 draw at Roots Hall for a 3-2 aggregate win. Veteran Shrimpers striker Neil Harris cancelled out Leitch-Smith's opener and skipper Chris Barker pulled another back with three minutes remaining.
"Wembley will be a fantastic opportunity for these young lads to put themselves on the big stage," said Davis. "For some of them, it is has come in their first season as a professional footballer. They have worked hard for it but they have great ability and they showed that tonight as they performed well."
The young Crewe side, who finished 11 points behind their opponents in seventh, held out during a nervy finish against Southend to book a promotion decider with Cheltenham or Torquay next weekend.
"We want to go all the way now. For us to get through these two games is a fantastic achievement because Southend had finished strong, like we did. Now we want to go to Wembley and win it."
Leitch-Smith opened the scoring in fine style after 24 minutes, cutting inside full-back Sean Clohessy before arrowing an angled drive past Cameron Belford.
After the break Harris slid Southend level on the night but Clayton, who had come on just 10 minutes earlier, went forward on the counter-attack in the 86th minute and tucked the ball inside Belford's far post.
Barker immediately pulled another back with a header but Southend, who also hit the woodwork twice and had a Freddy Eastwood goal disallowed, missed out on a first Wembley final in their history.
Manager Paul Sturrock said: "We can't afford to play like we did in the first 45 minutes and expect to get success. In the second half we had the aggression and appetite you need and if we had that from the start then it might have been a different game.
"We hit the post twice and had a goal disallowed but Crewe had chances as well and the bad goal we gave away in the first half hit us hard."