NAT a single IP using 2nd WAN Internet

RouterOS Beginner Basics
1

Hello,
I have a mikrotik RB750 (6.22) acting as a gateway for my LAN.
Here is the basic configuration:
Ether1-WAN1 (1.1.1.10/24) IPs are hidden for privacy
Ether2-WAN2 (2.2.2.20/24)
Ether5-LAN (192.168.1.1/24)

IP Routes:
AS 0.0.0.0/0 1.1.1.1 reachable on Ether1-WAN1 Distance 10
S 0.0.0.0/0 2.2.2.2 reachable on Ether2-WAN2 Distance 10

There are some port redirects which works fine. my Lan is using internet on WAN1 (it chose by default)
How can I configure a single IP address (a server) to NAT to 2.2.2.20 so it can use WAN2.?
I have created a srcnat to address 2.2.2.20. in whatismyip.com i see my IP changing to 2.2.2.20 but when I traceroute to any ip in internet, i see it goes out of 1.1.1.1

Thanks in advance