The Rams face a Wembley final against either Wigan or QPR to guarantee Premier League football, and former England boss McClaren is delighted with the progress the club have made in the Championship since his arrival in September.
Following the departure of Nigel Clough, with the club languishing in 14th, McClaren was appointed manager and has led Derby to a club record 85 points - securing third place in the Championship. A two-legged tie with Brighton & Hove Albion was the first obstacle to overcome in the search for the top flight, and, after a 2-1 away victory, McClaren masterminded a 4-1 home victory that was 'almost perfect' to the 53-year old.
Speaking after the game to Sky Sports, McClaren said: "We wanted a performance after a rather ugly 2-1 victory at Brighton, and boy did we get one.
"We were awesome, mixing energy and entertainment to thrill our wonderful supporters. We looked a damned good side and were almost perfect. If we can produce the same level of performance at Wembley, I reckon we can be a match for anybody."
Goals from Will Hughes, Chris Martin, George Thorne and Jeff Hendrick secured Derby's first return to Wembley since 2007, before a late Kazenga LuaLua finish took the sheen off the 'perfect' performance, and McClaren is delighted that he may be the man to bring Premier League football back to Derby.
"We're way ahead of schedule and if you'd have told me we'd make the play-offs at half-time of the first game against Ipswich in October, when we were 4-1 down, I wouldn't have believed you.
"I came here and signed for two-and-a-half years and said I wanted to build a football club. I wanted to get the fans back, the place buzzing again and a good brand of football on the field.
"The fans have appreciated that so they've been coming back and now there's a big buzz around the town. Stage one, for me, has been achieved.
"Jumping to stage two is a big step and we've got an opportunity. We've bought our lottery ticket to win something big. Can we do it? This is a big test for all of us."
Whether Derby can reclaim their top flight status - which they last had in a disastrous 2007/08 season - remains to be seen, although after their tremendous victory in the semi-finals, those involved at Pride Park will not be fearing the challenge of either Wigan Athletic or Queens Park Rangers.