Stuart McCall says it's "an honour and privilege" to be named as Rangers manager after agreeing to take over at Ibrox until the end of the season.
McCall replaces caretaker manager Kenny McDowall who left the club on Thursday.
"Obviously it's a big, big challenge, there's no doubt about that," said the former Motherwell boss.
"Anybody who has seen the side of late, the last three or four months, will know it's a big challenge, but ultimately it's a massive opportunity."
McCall returns to the Scottish Championship club, with whom he enjoyed a successful spell as a player from 1991 to 1998 - winning six league titles, three Scottish Cups and two Scottish League Cups.
Rangers are currently third in the table, five points behind second-place Hibernian and 22 behind league leaders Hearts.
"It's a great honour and privilege to be invited to come in and try to help the club at this moment in time, and something I'm really looking forward to," McCall added.
"The aim for us this season is to get out this league.
"Personally for me, it's great to get back out on the grass, on the coaching field, and we just look forward to progressing."
Rangers are chasing a third straight promotion as they seek a return to Scotland's top tier, but their promotion challenge has faltered this season under former manager Ally McCoist and McDowall.
"We're all under no illusions, we've under-performed this season for whatever reason, but there's enough quality in that dressing room to do better than what we've done," said McCall, whose Motherwell side finished runners-up to Celtic in the Premiership last season.
"Football can change so quickly. There's no magic pill, there's no magic formula for confidence, and obviously that's severely lacking at this moment in time.
"A new voice can give certain players a spark. I think there are 12 boys out of contract, but the message to them and to everyone is - go and win yourself a contract."
|McCall's Rangers playing career|
|Joined from Everton in 1991||Helped side win league and cup double within a year|
|Part of Rangers' treble winning side of 1992-93||Won four further league titles as part of Walter Smith's team|
|Also picked up two more cup medals||Left Ibrox to join Bradford City in 1998|
A run of one win in seven matches in all competitions has caused anger among the club's support towards their under-achieving team, and McCall says it is up to the players to win back the fans' trust.
"The supporters don't want to come and boo and criticise, they want to get behind the team.
"This club's been kicked for too long. We need to flip this around.
"There's still enough games to do it, and everyone who goes out on the park must believe that this can still be a successful season.
"They've had back-to-back promotions - go and make it a third."
McCall's appointment at Ibrox on a short-term basis leaves his future as part of Gordon Strachan's Scotland coaching staff unclear.
"I spoke to Gordon at length and he was fantastic," McCall continued.
"I explained the situation. Obviously the games coming up, Northern Ireland and Gibraltar, I won't be involved for that, but I'm sure Gordon will make a statement next week when he names the squad and there'll be more.
"My contract here will finish in the summer. If I don't get offered another one then there might be an opportunity to work with Scotland."